diff --git a/examples/custom_filters.py b/examples/custom_filters.py
new file mode 100644
index 0000000..23cebe3
--- /dev/null
+++ b/examples/custom_filters.py
@@ -0,0 +1,46 @@
+import telebot
+from telebot import util
+
+bot = telebot.TeleBot('TOKEN')
+
+
+# AdvancedCustomFilter is for list, string filter values
+class MainFilter(util.AdvancedCustomFilter):
+    key='text'
+    @staticmethod
+    def check(message, text):
+        return message.text in text
+
+# SimpleCustomFilter is for boolean values, such as is_admin=True
+class IsAdmin(util.SimpleCustomFilter):
+    key='is_admin'
+    @staticmethod
+    def check(message: telebot.types.Message):
+        if bot.get_chat_member(message.chat.id,message.from_user.id).status in ['administrator','creator']:
+            return True
+        else:
+            return False
+
+
+@bot.message_handler(is_admin=True, commands=['admin']) # Check if user is admin
+def admin_rep(message):
+    bot.send_message(message.chat.id, "Hi admin")
+
+@bot.message_handler(is_admin=False, commands=['admin']) # If user is not admin
+def not_admin(message):
+    bot.send_message(message.chat.id, "You are not admin")
+
+@bot.message_handler(text=['hi']) # Response to hi message
+def welcome_hi(message):
+    bot.send_message(message.chat.id, 'You said hi')
+
+@bot.message_handler(text=['bye']) # Response to bye message
+def bye_user(message):
+    bot.send_message(message.chat.id, 'You said bye')
+
+
+# Do not forget to register filters
+bot.add_custom_filter(MainFilter)
+bot.add_custom_filter(IsAdmin)
+
+bot.polling(skip_pending=True) # Skip old updates
\ No newline at end of file
diff --git a/telebot/__init__.py b/telebot/__init__.py
index e379435..5816cdf 100644
--- a/telebot/__init__.py
+++ b/telebot/__init__.py
@@ -3140,9 +3140,9 @@ class TeleBot:
         filter_check = self.custom_filters.get(message_filter)
         if not filter_check:
             return False
-        elif isinstance(filter_check, util.SimpleCustomFilter):
+        elif isinstance(filter_check(), util.SimpleCustomFilter):
             return filter_value == filter_check.check(message)
-        elif isinstance(filter_check, util.AdvancedCustomFilter):
+        elif isinstance(filter_check(), util.AdvancedCustomFilter):
             return filter_check.check(message, filter_value)
         else:
             logger.error("Custom filter: wrong type. Should be SimpleCustomFilter or AdvancedCustomFilter.")