diff --git a/homeassistant/components/telegram_bot/__init__.py b/homeassistant/components/telegram_bot/__init__.py
index b59c9ae84e8..434c03fb181 100644
--- a/homeassistant/components/telegram_bot/__init__.py
+++ b/homeassistant/components/telegram_bot/__init__.py
@@ -543,9 +543,10 @@ class BaseTelegramBotEntity:
 
         data = {
             ATTR_USER_ID: msg_data['from']['id'],
-            ATTR_FROM_FIRST: msg_data['from']['first_name'],
-            ATTR_FROM_LAST: msg_data['from']['last_name']
+            ATTR_FROM_FIRST: msg_data['from']['first_name']
         }
+        if 'last_name' in msg_data['from']:
+            data[ATTR_FROM_LAST] = msg_data['from']['last_name']
         if 'chat' in msg_data:
             data[ATTR_CHAT_ID] = msg_data['chat']['id']