A method, a system, a security device, a service control device, and a communication terminal for providing a Multimedia Broadcast/Multicast Service (MBMS) service are provided. The method includes the following steps: A service control module in an IP Multimedia Subsystem (IMS) system carries out service authorization according to a service authorization request, and obtains an authorization-passed result. The service control module sends the authorization-passed result to a security module. The security module obtains the authorization-passed result and then sends a service decryption code of the MBMS service to UEs. In the present invention, a controlling capacity of an IMS and a bearer capacity of an MBMS are multiplexed based on an IMS system and an MBMS system to achieve IPTV services, so as to achieve the uniform authorization and uniform network management. The binding of the IPTV service with other services based on the IMS can be achieved by using the IMS, and personalized services can be provided to UEs.