diff --git a/pyrogram/client/types/bots/callback_query.py b/pyrogram/client/types/bots/callback_query.py
index 30a5333f..767d768c 100644
--- a/pyrogram/client/types/bots/callback_query.py
+++ b/pyrogram/client/types/bots/callback_query.py
@@ -79,7 +79,7 @@ class CallbackQuery(PyrogramType, Update):
         self.chat_instance = chat_instance
         self.message = message
         self.inline_message_id = inline_message_id
-        self.data = data
+        self.data: str = str(data, "utf-8")
         self.game_short_name = game_short_name
 
     @staticmethod
diff --git a/pyrogram/client/types/bots/inline_keyboard_button.py b/pyrogram/client/types/bots/inline_keyboard_button.py
index c0c3eb8c..5e225846 100644
--- a/pyrogram/client/types/bots/inline_keyboard_button.py
+++ b/pyrogram/client/types/bots/inline_keyboard_button.py
@@ -15,6 +15,7 @@
 #
 # You should have received a copy of the GNU Lesser General Public License
 # along with Pyrogram.  If not, see <http://www.gnu.org/licenses/>.
+from typing import Union
 
 from pyrogram.api.types import (
     KeyboardButtonUrl, KeyboardButtonCallback,
@@ -61,7 +62,7 @@ class InlineKeyboardButton(PyrogramType):
     def __init__(
         self,
         text: str,
-        callback_data: bytes = None,
+        callback_data: Union[str, bytes] = None,
         url: str = None,
         switch_inline_query: str = None,
         switch_inline_query_current_chat: str = None,
@@ -71,7 +72,7 @@ class InlineKeyboardButton(PyrogramType):
 
         self.text = str(text)
         self.url = url
-        self.callback_data = callback_data
+        self.callback_data = bytes(callback_data, "utf-8") if isinstance(callback_data, str) else callback_data
         self.switch_inline_query = switch_inline_query
         self.switch_inline_query_current_chat = switch_inline_query_current_chat
         self.callback_game = callback_game