A policy control method for a converged network comprises: in a roaming scenario, after learning that a user equipment (UE) accesses a mobile network through a wireless local area network (WLAN) access, a visited policy and charging rules function (V-PCRF) establishing a subsession serving WLAN Offload when establishing an S9 session to a home policy and charging rules function (H-PCRF), and carrying a WLAN Offload instruction. With the present document, the WLAN offload data can be distinguished from data routed back to an EPC network in the roaming scenario, thereby delivering policy control for the WLAN offload data.