A UE capability reporting method is provided to resolve a problem that when UE is handed over from a source access network device to a target access network device, UE capability information obtained by the target access network device is incomplete. A solution is as follows: UE obtains first information, where the first information is used to indicate a UE capability supported by a target access network device; and the UE reports second information based on the UE capability supported by the target access network device and a UE capability of the UE, where the second information includes capability information, other than UE capability information stored in a source access network device, in target capability information, and the target capability information is UE capability information of a lower UE capability in the UE capability of the UE and the UE capability supported by the target access network device.