diff --git a/telethon/types/_custom/button.py b/telethon/types/_custom/button.py
index ffac7c99..27f1aae9 100644
--- a/telethon/types/_custom/button.py
+++ b/telethon/types/_custom/button.py
@@ -1,6 +1,8 @@
+import typing
+
 from .messagebutton import MessageButton
 from ... import _tl
-from ..._misc import utils
+from ..._misc import utils, hints
 
 
 class Button:
@@ -54,6 +56,7 @@ class Button:
             _tl.KeyboardButtonCallback,
             _tl.KeyboardButtonGame,
             _tl.KeyboardButtonSwitchInline,
+            _tl.KeyboardButtonUserProfile,
             _tl.KeyboardButtonUrl,
             _tl.InputKeyboardButtonUrlAuth
         ))
@@ -166,6 +169,29 @@ class Button:
             fwd_text=fwd_text
         )
 
+    @staticmethod
+    def mention(text, input_entity):
+        """
+        Creates a new inline button linked to the profile of user.
+
+        Args:
+            input_entity:
+                Input entity of :tl:User to use for profile button.
+                By default, this is the logged in user (itself), although
+                you may pass a different input peer.
+
+                .. note::
+
+                    For now, you cannot use ID or username for this argument.
+                    If you want to use different user, you must manually use
+                    `client.get_input_entity() <telethon.client.users.UserMethods.get_input_entity>`.
+        """
+        return _tl.InputKeyboardButtonUserProfile(
+            text,
+            utils.get_input_user(input_entity or _tl.InputUserSelf())
+        )
+
+
     @classmethod
     def text(cls, text, *, resize=None, single_use=None, selective=None):
         """
@@ -387,4 +413,4 @@ def build_reply_markup(
         return _tl.ReplyInlineMarkup(rows)
     # elif is_normal:
     return _tl.ReplyKeyboardMarkup(
-        rows, resize=resize, single_use=single_use, selective=selective)
+        rows, resize=resize, single_use=single_use, selective=selective)
\ No newline at end of file
diff --git a/telethon/types/_custom/messagebutton.py b/telethon/types/_custom/messagebutton.py
index 2d588727..eee4486e 100644
--- a/telethon/types/_custom/messagebutton.py
+++ b/telethon/types/_custom/messagebutton.py
@@ -71,6 +71,10 @@ class MessageButton:
         If it's an inline :tl:`KeyboardButtonCallback` with text and data,
         it will be "clicked" and the :tl:`BotCallbackAnswer` returned.
 
+        If it's an inline :tl:`KeyboardButtonUserProfile` button, the
+        `client.get_entity` will be called and the resulting :tl:User will be
+        returned.
+
         If it's an inline :tl:`KeyboardButtonSwitchInline` button, the
         :tl:`StartBot` will be invoked and the resulting updates
         returned.
@@ -107,6 +111,8 @@ class MessageButton:
                 return await self._client(req)
             except BotResponseTimeoutError:
                 return None
+        elif isinstance(self.button, _tl.KeyboardButtonUserProfile):
+            return await self._client.get_entity(self.button.user_id)
         elif isinstance(self.button, _tl.KeyboardButtonSwitchInline):
             return await self._client(_tl.fn.messages.StartBot(
                 bot=self._bot, peer=self._chat, start_param=self.button.query
@@ -143,4 +149,4 @@ class MessageButton:
                 long, lat = share_geo
                 share_geo = _tl.InputMediaGeoPoint(_tl.InputGeoPoint(lat=lat, long=long))
 
-            return await self._client.send_file(self._chat, share_geo)
+            return await self._client.send_file(self._chat, share_geo)
\ No newline at end of file