The present invention discloses a method and a system for implementing domain selection during a terminated call, wherein, the method comprises: an application server (AS) sending, according to a received call request message, a query request message to a home subscriber server (HSS); the HSS querying, according to the query request message, a packet switching (PS) domain mobility management network element to obtain information of a called terminal and/or a network accessed by the called terminal in the call request message; the HSS feeding back the obtained information of the called terminal and/or the network accessed by the called terminal to the AS; and the AS selecting a domain to which a call message is to be routed according to the information of the called terminal and/or the network accessed by the called terminal. The present invention can greatly reduce the number of the signalings between the PS domain mobility management element and the HSS, avoids various limitations of the signaling loads generated by the HSS on network deployment, is convenient for the network deployment, and ensures the implementation of services.