Question: Can I pass an integer parameter (an NSString for example) in action:@selector(ActionMethod:) 

The action is related to a UIButton

Thanks !

Answer: 
No, the action methods are called passing in the UIButton (or other UIControl) as the only parameter. However, you can subclass UIButton and add instance variables, then save you string in the button. When the action method is called you can access the string.
Use a map to save the mapping between tag and NSString. When you want some data from the UIButton, get the tag and then search the mapping table to get the related NSString.