diff --git a/edapi/edapi.py b/edapi/edapi.py
index ebb429f..f840f9c 100644
--- a/edapi/edapi.py
+++ b/edapi/edapi.py
@@ -12,7 +12,7 @@
 
 from edapi.types.api_types.endpoints.analytics import API_Analytics_Users_Response
 
-from .types import EdAuthError, EdError, EditThreadParams, PostThreadParams
+from .types import EdAuthError, EdError, EditThreadParams, PostThreadParams, PostCommentParams
 from .types.api_types.endpoints.activity import (
     API_ListUserActivity_Response,
     API_ListUserActivity_Response_Item,
@@ -302,6 +302,20 @@ def post_thread(
 
         _throw_error(f"Failed to post thread in course {course_id}.", response.content)
 
+    @_ensure_login
+    def post_comment(
+        self, thread_id: int, params: PostCommentParams
+    ):
+        """
+        Creates a new comment under the given thread.
+
+        POST /api/threads/<thread_id>/comments
+        """
+        thread_url = urljoin(API_BASE_URL, f"threads/{thread_id}/comments")
+        response = self.session.post(thread_url, json={"comment": params})
+        if not response.ok:
+            _throw_error(f"Failed to post comment in thread {thread_id}.", response.content)
+
     @_ensure_login
     def edit_thread(
         self, thread_id: int, params: EditThreadParams, unlock_thread=True
diff --git a/edapi/types/types.py b/edapi/types/types.py
index 04fd126..038871c 100644
--- a/edapi/types/types.py
+++ b/edapi/types/types.py
@@ -53,3 +53,13 @@ class PostThreadParams(TypedDict, total=True):
     is_anonymous: bool
     is_megathread: bool
     anonymous_comments: bool
+
+class PostCommentParams(TypedDict, total=True):
+    """
+    Parameters for posting a new comment.
+    All parameters are required.
+    """
+    content: str
+    is_anonymous: bool
+    is_private: bool
+    type: str