A scheduling server receives a voice service group access request from a user terminal, wherein the voice service group access request carries an identifier of a voice service group that a user of the user terminal is to join. The scheduling server determines a candidate voice server set according to a region where the user terminal is located and/or a network operator of the user terminal. If the number of online users in the voice service group identified by the identifier in the voice service group access request does not exceed a predefined threshold, a relationship between the voice service group and a first voice server providing services for the voice service group is found in a storage area and the first voice server belongs to the candidate voice server set, the user terminal accesses the voice service group via the first voice server.