An instant messaging communication system including information terminals and an instant messaging server is provided. The information terminals are configurable for use by searching users or search target users. The information terminal of a searching user acquires, from the instant messaging server, search target user information, and searches the search target user information for a search target user matching a profile created by the searching user. The information terminal of a search target user registers the search target user profile with the instant messenger server. The instant messenger server is a conduit among the searching users and the search target users, automatically sending updated information to the searching users upon registering a new search target user or updating the information of a search target user. Because the terminals perform the search and the server acts as a conduit, reliability and efficiency of the instant messenger network is improved.