A mobile terminal is capable of updating user presence information in mobile instant messaging. The mobile terminal and associated method facilitate updating user presence information in multiple sessions of mobile instant messaging. The method includes: joining multiple IM communities; issuing a command for presence information update in relation to one of the multiple IM communities; and sending a request for presence information update to IM servers of two or more IM communities including the IM community indicated by the issued update command, among the multiple IM communities.