A method and a system for feeding a service state information back are disclosed, which are applied to a multimedia broadcasting/multicasting service system. The method comprises steps as follows: after an event triggered is detected, a user equipment transmits uplink feedback signaling with the service state information of the user equipment to a coordinating entity in a region where the user equipment locates(101); the coordinating entity re-assigns network resources to the user equipments in its region of right according to the uplink feedback signaling(102). The system comprises: user equipments, base station nodes and the coordinating entities. According the solution, when the event is triggered, the user equipment forwardly transmits the uplink feedback signaling so as to assign the network resources, thereby it is unnecessary to periodically use the polling mechanism to statistically count the user equipments, then the system resources engrossed due to the periodical polling are reduced. In addition, the system can simultaneously obtain the service information and application information.