Methods and devices for management of group user data and/or maintenance of instant messaging groups. The methods may include receiving, by a computing device, a request for searching data of a first group user. For example, the request is initialized by a second group user via an instant messaging application. The computing device may determine a data search permission of the second group user on the data of the first group user, select a data item of the first group user in accordance with the data search permission, and return the data item to the second group user. Using techniques described herein, the implementations may enable users to view group contacts and perform access control to improve security of the group data and to avoid leakage of communication information of group users.