A method and system for participating in a group call are provided in the present invention. The method includes: after receiving a request of registering a temporary dispatcher sent by a user, an anchor mobile switching centre initiating a registration request, which includes a group call reference number and a registration number required to be registered by the user, to a group call register; after receiving a group call message related to the group call reference number, the anchor mobile switching centre using the temporary dispatcher's number registered by the group call register to establish a call to the group call corresponding to the group call reference number. With the present invention, it enables a service subscriber who does not support call forwarding and a dispatcher who is in abnormal conditions of power failure or entering a blind zone to continue to participate in corresponding group calls.