diff --git a/app/controllers/comments_controller.rb b/app/controllers/comments_controller.rb
index c388c72a..7ae65358 100644
--- a/app/controllers/comments_controller.rb
+++ b/app/controllers/comments_controller.rb
@@ -15,9 +15,11 @@ class CommentsController < ApplicationController
     comment = Comment.new(comment_params)
 
     if comment.save
-      render json: comment, status: :no_content
+      render json: comment, status: :created
     else
-      render json: I18n.t('errors.unauthorized'), status: :unauthorized
+      render json: {
+        error: I18n.t('errors.comment.create', message: comment.errors.full_messages)
+      }, status: :unprocessable_entity
     end
   end
 
@@ -26,7 +28,7 @@ class CommentsController < ApplicationController
     def comment_params
       params
         .require(:comment)
-        .permit(:body)
+        .permit(:body, :parent_id)
         .merge(
           user_id: current_user.id,
           post_id: params[:post_id]
diff --git a/app/javascript/actions/submitComment.ts b/app/javascript/actions/submitComment.ts
new file mode 100644
index 00000000..b7cd5c82
--- /dev/null
+++ b/app/javascript/actions/submitComment.ts
@@ -0,0 +1,82 @@
+import { Action } from 'redux';
+import { ThunkAction } from 'redux-thunk';
+import { State } from '../reducers/rootReducer';
+
+import ICommentJSON from '../interfaces/json/IComment';
+
+export const COMMENT_SUBMIT_START = 'COMMENT_SUBMIT_START';
+interface CommentSubmitStartAction {
+  type: typeof COMMENT_SUBMIT_START;
+  parentId: number;
+}
+
+export const COMMENT_SUBMIT_SUCCESS = 'COMMENT_SUBMIT_SUCCESS';
+interface CommentSubmitSuccessAction {
+  type: typeof COMMENT_SUBMIT_SUCCESS;
+  comment: ICommentJSON;
+}
+
+export const COMMENT_SUBMIT_FAILURE = 'COMMENT_SUBMIT_FAILURE';
+interface CommentSubmitFailureAction {
+  type: typeof COMMENT_SUBMIT_FAILURE;
+  parentId: number;
+  error: string;
+}
+
+export type CommentSubmitActionTypes =
+  CommentSubmitStartAction |
+  CommentSubmitSuccessAction |
+  CommentSubmitFailureAction;
+
+const commentSubmitStart = (parentId): CommentSubmitStartAction => ({
+  type: COMMENT_SUBMIT_START,
+  parentId,
+});
+
+const commentSubmitSuccess = (
+  commentJSON: ICommentJSON,
+): CommentSubmitSuccessAction => ({
+  type: COMMENT_SUBMIT_SUCCESS,
+  comment: commentJSON,
+});
+
+const commentSubmitFailure = (parentId, error): CommentSubmitFailureAction => ({
+  type: COMMENT_SUBMIT_FAILURE,
+  parentId,
+  error,
+});
+
+export const submitComment = (
+  postId,
+  body,
+  parentId,
+  authenticityToken,
+): ThunkAction<void, State, null, Action<string>> => async (dispatch) => {
+  dispatch(commentSubmitStart(parentId));
+
+  try {
+    const res = await fetch(`/posts/${postId}/comments`, {
+      method: 'POST',
+      headers: {
+        Accept: 'application/json',
+        'Content-Type': 'application/json',
+        'X-CSRF-Token': authenticityToken,
+      },
+      body: JSON.stringify({
+        comment: {
+          body,
+          parent_id: parentId,
+        },
+      }),
+    });
+    const json = await res.json();
+
+    if (res.status === 201) {
+      dispatch(commentSubmitSuccess(json));
+    } else {
+      dispatch(commentSubmitFailure(parentId, json.error));
+    }
+  } catch (e) {
+    dispatch(commentSubmitFailure(parentId, e));
+  }
+}
\ No newline at end of file
diff --git a/app/javascript/components/Comments/Comment.tsx b/app/javascript/components/Comments/Comment.tsx
index 76ec5ac9..4f05be55 100644
--- a/app/javascript/components/Comments/Comment.tsx
+++ b/app/javascript/components/Comments/Comment.tsx
@@ -1,6 +1,7 @@
 import * as React from 'react';
 import { FormEvent } from 'react';
 
+import NewComment from './NewComment';
 import { MutedText } from '../shared/CustomTexts';
 
 import { CommentRepliesState } from '../../reducers/commentRepliesReducer';
@@ -16,6 +17,7 @@ interface Props {
   reply: CommentRepliesState;
   handleToggleCommentReply(): void;
   handleCommentReplyBodyChange(e: FormEvent): void;
+  handleSubmitComment(body: string, parentId: number): void;
 }
 
 const Comment = ({
@@ -29,6 +31,7 @@ const Comment = ({
   reply,
   handleToggleCommentReply,
   handleCommentReplyBodyChange,
+  handleSubmitComment,
 }: Props) => (
   <div className="comment">
     <div className="commentHeader">
@@ -41,9 +44,11 @@ const Comment = ({
     </div>
     {
       reply.isOpen ?
-        <textarea
-          value={reply.body}
-          onChange={handleCommentReplyBodyChange}
+        <NewComment
+          body={reply.body}
+          parentId={id}
+          handleChange={handleCommentReplyBodyChange}
+          handleSubmit={handleSubmitComment}
         />
         :
         null
diff --git a/app/javascript/components/Comments/CommentList.tsx b/app/javascript/components/Comments/CommentList.tsx
index df122c34..674409f1 100644
--- a/app/javascript/components/Comments/CommentList.tsx
+++ b/app/javascript/components/Comments/CommentList.tsx
@@ -12,8 +12,9 @@ interface Props {
   parentId: number;
   level: number;
 
-  toggleCommentReply(commentId: number);
-  setCommentReplyBody(commentId: number, body: string);
+  toggleCommentReply(commentId: number): void;
+  setCommentReplyBody(commentId: number, body: string): void;
+  handleSubmitComment(body: string, parentId: number): void;
 }
 
 const CommentList = ({
@@ -24,12 +25,13 @@ const CommentList = ({
 
   toggleCommentReply,
   setCommentReplyBody,
+  handleSubmitComment,
 }: Props) => (
   <React.Fragment>
     {comments.map((comment, i) => {
       if (comment.parentId === parentId) {
         return (
-          <div className="commentList">
+          <div className="commentList" key={i}>
             <Comment
               level={level}
               reply={replies.find(reply => reply.commentId === comment.id)}
@@ -39,6 +41,7 @@ const CommentList = ({
                   setCommentReplyBody(comment.id, (e.target as HTMLTextAreaElement).value)
                 )
               }
+              handleSubmitComment={handleSubmitComment}
               {...comment}
             />
 
@@ -50,6 +53,7 @@ const CommentList = ({
 
               toggleCommentReply={toggleCommentReply}
               setCommentReplyBody={setCommentReplyBody}
+              handleSubmitComment={handleSubmitComment}
             />
           </div>
         );
diff --git a/app/javascript/components/Comments/CommentsP.tsx b/app/javascript/components/Comments/CommentsP.tsx
index 087e18a6..a5ea8aa1 100644
--- a/app/javascript/components/Comments/CommentsP.tsx
+++ b/app/javascript/components/Comments/CommentsP.tsx
@@ -1,5 +1,7 @@
 import * as React from 'react';
+import { FormEvent } from 'react';
 
+import NewComment from './NewComment';
 import CommentList from './CommentList';
 import Spinner from '../shared/Spinner';
 import { DangerText } from '../shared/CustomTexts';
@@ -9,15 +11,22 @@ import { CommentRepliesState } from '../../reducers/commentRepliesReducer';
 
 interface Props {
   postId: number;
+  authenticityToken: string;
 
   comments: Array<IComment>;
   replies: Array<CommentRepliesState>;
   areLoading: boolean;
   error: string;
 
-  requestComments(postId: number, page?: number);
-  toggleCommentReply(commentId: number);
-  setCommentReplyBody(commentId: number, body: string);
+  requestComments(postId: number, page?: number): void;
+  toggleCommentReply(commentId: number): void;
+  setCommentReplyBody(commentId: number, body: string): void;
+  submitComment(
+    postId: number,
+    body: string,
+    parentId: number,
+    authenticityToken: string,
+  ): void;
 }
 
 class CommentsP extends React.Component<Props> {
@@ -25,6 +34,15 @@ class CommentsP extends React.Component<Props> {
     this.props.requestComments(this.props.postId);
   }
 
+  _handleSubmitComment = (body, parentId) => {
+    this.props.submitComment(
+      this.props.postId,
+      body,
+      parentId,
+      this.props.authenticityToken,
+    );
+  }
+
   render() {
     const {
       comments,
@@ -34,12 +52,24 @@ class CommentsP extends React.Component<Props> {
 
       toggleCommentReply,
       setCommentReplyBody,
+      submitComment,
     } = this.props;
 
     return (
       <div className="comments">
         <h2>Comments</h2>
 
+        <NewComment
+          body={replies.find(reply => reply.commentId === -1) && replies.find(reply => reply.commentId === -1).body}
+          parentId={null}
+          handleChange={
+            (e: FormEvent) => (
+              setCommentReplyBody(-1, (e.target as HTMLTextAreaElement).value)
+            )
+          }
+          handleSubmit={this._handleSubmitComment}
+        />
+
         { areLoading ? <Spinner /> : null }
         { error ? <DangerText>{error}</DangerText> : null }
 
@@ -48,6 +78,7 @@ class CommentsP extends React.Component<Props> {
           replies={replies}
           toggleCommentReply={toggleCommentReply}
           setCommentReplyBody={setCommentReplyBody}
+          handleSubmitComment={this._handleSubmitComment}
           parentId={null}
           level={1}
         />
diff --git a/app/javascript/components/Comments/NewComment.tsx b/app/javascript/components/Comments/NewComment.tsx
new file mode 100644
index 00000000..c68a4167
--- /dev/null
+++ b/app/javascript/components/Comments/NewComment.tsx
@@ -0,0 +1,28 @@
+import * as React from 'react';
+import { FormEvent } from 'react';
+
+import Button from '../shared/Button';
+
+interface Props {
+  body: string;
+  parentId: number;
+  handleChange(e: FormEvent): void;
+  handleSubmit(body: string, parentId: number): void;
+}
+
+const NewComment = ({
+  body,
+  parentId,
+  handleChange,
+  handleSubmit,
+}: Props) => (
+  <div className="newCommentForm">
+    <textarea
+      value={body}
+      onChange={handleChange}
+    />
+    <Button onClick={() => handleSubmit(body, parentId)}>Submit</Button>
+  </div>
+);
+
+export default NewComment;
\ No newline at end of file
diff --git a/app/javascript/components/Post/PostP.tsx b/app/javascript/components/Post/PostP.tsx
index 70e0ebde..5b58100e 100644
--- a/app/javascript/components/Post/PostP.tsx
+++ b/app/javascript/components/Post/PostP.tsx
@@ -59,7 +59,10 @@ class PostP extends React.Component<Props> {
 
         <p>{post.description}</p>
 
-        <Comments postId={this.props.postId} />
+        <Comments
+          postId={this.props.postId}
+          authenticityToken={authenticityToken}
+        />
       </div>
     );
   }
diff --git a/app/javascript/containers/Comments.tsx b/app/javascript/containers/Comments.tsx
index 0a3a19b8..ccf592d5 100644
--- a/app/javascript/containers/Comments.tsx
+++ b/app/javascript/containers/Comments.tsx
@@ -5,6 +5,7 @@ import {
   toggleCommentReply,
   setCommentReplyBody,
 } from '../actions/handleCommentReplies';
+import { submitComment } from '../actions/submitComment';
 
 import { State } from '../reducers/rootReducer';
 
@@ -29,6 +30,15 @@ const mapDispatchToProps = (dispatch) => ({
   setCommentReplyBody(commentId: number, body: string) {
     dispatch(setCommentReplyBody(commentId, body));
   },
+
+  submitComment(
+    postId: number,
+    body: string,
+    parentId: number,
+    authenticityToken: string,
+  ) {
+    dispatch(submitComment(postId, body, parentId, authenticityToken));
+  },
 });
 
 export default connect(
diff --git a/app/javascript/reducers/commentRepliesReducer.ts b/app/javascript/reducers/commentRepliesReducer.ts
index 185f6dbc..31033942 100644
--- a/app/javascript/reducers/commentRepliesReducer.ts
+++ b/app/javascript/reducers/commentRepliesReducer.ts
@@ -1,22 +1,33 @@
 import {
   COMMENT_REQUEST_SUCCESS,
 } from '../actions/requestComment';
+
 import {
   HandleCommentRepliesType,
   TOGGLE_COMMENT_REPLY,
   SET_COMMENT_REPLY_BODY,
 } from '../actions/handleCommentReplies';
 
+import {
+  COMMENT_SUBMIT_START,
+  COMMENT_SUBMIT_SUCCESS,
+  COMMENT_SUBMIT_FAILURE,
+} from '../actions/submitComment';
+
 export interface CommentRepliesState {
   commentId: number;
   isOpen: boolean;
   body: string;
+  isSubmitting: boolean;
+  error: string;
 }
 
 const initialState: CommentRepliesState = {
   commentId: undefined,
   isOpen: false,
   body: '',
+  isSubmitting: false,
+  error: '',
 }
 
 const commentRepliesReducer = (
@@ -42,6 +53,27 @@ const commentRepliesReducer = (
         body: action.body,
       };
 
+    case COMMENT_SUBMIT_START:
+      return {
+        ...state,
+        isSubmitting: true,
+      };
+
+    case COMMENT_SUBMIT_SUCCESS:
+      return {
+        ...state,
+        isOpen: false,
+        body: '',
+        isSubmitting: false,
+        error: '',
+      };
+
+    case COMMENT_SUBMIT_FAILURE:
+      return {
+        ...state,
+        error: action.error,
+      };
+
     default:
       return state;
   }
diff --git a/app/javascript/reducers/commentsReducer.ts b/app/javascript/reducers/commentsReducer.ts
index 2d34a4d8..1be92a9a 100644
--- a/app/javascript/reducers/commentsReducer.ts
+++ b/app/javascript/reducers/commentsReducer.ts
@@ -13,6 +13,12 @@ import {
   SET_COMMENT_REPLY_BODY,
 } from '../actions/handleCommentReplies';
 
+import {
+  COMMENT_SUBMIT_START,
+  COMMENT_SUBMIT_SUCCESS,
+  COMMENT_SUBMIT_FAILURE,
+} from '../actions/submitComment';
+
 import commentReducer from './commentReducer';
 import commentRepliesReducer from './commentRepliesReducer';
 
@@ -50,9 +56,10 @@ const commentsReducer = (
         items: action.comments.map(
           comment => commentReducer(undefined, commentRequestSuccess(comment))
         ),
-        replies: action.comments.map(
-          comment => commentRepliesReducer(undefined, commentRequestSuccess(comment))
-        ),
+        replies: [commentRepliesReducer(undefined, {type: 'COMMENT_REQUEST_SUCCESS', comment: { id: -1 } }),
+          ...action.comments.map(
+            comment => commentRepliesReducer(undefined, commentRequestSuccess(comment))
+        )],
         areLoading: false,
         error: '',
       };
@@ -78,6 +85,38 @@ const commentsReducer = (
         ),
       };
 
+    case COMMENT_SUBMIT_START:
+    case COMMENT_SUBMIT_FAILURE:
+      return {
+        ...state,
+        replies: state.replies.map(
+          reply => (
+            reply.commentId === action.parentId ?
+              commentRepliesReducer(reply, action)
+            :
+              reply
+          )
+        ),
+      };
+
+    case COMMENT_SUBMIT_SUCCESS:
+      console.log(action.comment);
+      return {
+        ...state,
+        items: [commentReducer(undefined, commentRequestSuccess(action.comment)), ...state.items],
+        replies: [
+          ...state.replies.map(
+            reply => (
+              reply.commentId === action.comment.parent_id ?
+                commentRepliesReducer(reply, action)
+              :
+                reply
+            )
+          ),
+          commentRepliesReducer(undefined, commentRequestSuccess(action.comment)),
+        ],
+      };
+
     default:
       return state;
   }
diff --git a/app/javascript/reducers/currentPostReducer.ts b/app/javascript/reducers/currentPostReducer.ts
index 35632d03..2f721cb0 100644
--- a/app/javascript/reducers/currentPostReducer.ts
+++ b/app/javascript/reducers/currentPostReducer.ts
@@ -23,6 +23,13 @@ import {
   SET_COMMENT_REPLY_BODY,
 } from '../actions/handleCommentReplies';
 
+import {
+  CommentSubmitActionTypes,
+  COMMENT_SUBMIT_START,
+  COMMENT_SUBMIT_SUCCESS,
+  COMMENT_SUBMIT_FAILURE,
+} from '../actions/submitComment';
+
 import postReducer from './postReducer';
 import commentsReducer from './commentsReducer';
 
@@ -50,7 +57,8 @@ const currentPostReducer = (
     PostRequestActionTypes |
     ChangePostStatusSuccessAction |
     CommentsRequestActionTypes |
-    HandleCommentRepliesType
+    HandleCommentRepliesType |
+    CommentSubmitActionTypes
 ): CurrentPostState => {
   switch (action.type) {
     case POST_REQUEST_START:
@@ -85,6 +93,9 @@ const currentPostReducer = (
     case COMMENTS_REQUEST_FAILURE:
     case TOGGLE_COMMENT_REPLY:
     case SET_COMMENT_REPLY_BODY:
+    case COMMENT_SUBMIT_START:
+    case COMMENT_SUBMIT_SUCCESS:
+    case COMMENT_SUBMIT_FAILURE:
       return {
         ...state,
         comments: commentsReducer(state.comments, action),
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 12a1b3e5..16d67d31 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -3,4 +3,6 @@ en:
     unauthorized: 'You are not authorized'
     post:
       create: 'Post create error: %{message}'
-      update: 'Post update error: %{message}'
\ No newline at end of file
+      update: 'Post update error: %{message}'
+    comment:
+      create: 'Comment create error: %{message}'
\ No newline at end of file