A mobile communication method, comprising: sending, by user equipment, UE, an attach request message to a mobility management entity; wherein the attach request message sent by the UE comprises a UE security capability; receiving (S31), by the UE, a non-access stratum, NAS, security mode command message from the mobility management entity, wherein the NAS security mode command message carries first verification matching information, an integrity algorithm used by the mobility management entity, a key identifier, and a first non-access stratum message authentication code, NAS-MAC, of the NAS security mode command message and a UE security capability sent back by the mobility management entity; wherein the first verification matching information comprises a first hash value of an attach request message that is received by the mobility management entity; calculating (S32), by the UE, a second NAS-MAC of the NAS security mode command message received from the mobility management entity, and a second hash value of the attach request message sent by the UE; determining (S33, S34), by the UE, whether the second hash value is consistent with the first hash value , the second NAS-MAC is consistent with the first NAS-MAC and the UE security capability sent back by the mobility management entity is consistent with the UE security capability carried in the attach request message sent by the UE ; and if the second hash value is consistent with the first hash value, the second NAS-MAC is consistent with the first NAS-MAC and the UE security capability sent back by the mobility management entity is consistent with the UE security capability carried in the attach request message sent by the UE, sending (S35), by the UE, a NAS security mode complete message to the mobility management entity. sending, by user equipment, UE, an attach request message to a mobility management entity; wherein the attach request message sent by the UE comprises a UE security capability; receiving (S31), by the UE, a non-access stratum, NAS, security mode command message from the mobility management entity, wherein the NAS security mode command message carries first verification matching information, an integrity algorithm used by the mobility management entity, a key identifier, and a first non-access stratum message authentication code, NAS-MAC, of the NAS security mode command message and a UE security capability sent back by the mobility management entity; wherein the first verification matching information comprises a first hash value of an attach request message that is received by the mobility management entity; calculating (S32), by the UE, a second NAS-MAC of the NAS security mode command message received from the mobility management entity, and a second hash value of the attach request message sent by the UE; determining (S33, S34), by the UE, whether the second hash value is consistent with the first hash value , the second NAS-MAC is consistent with the first NAS-MAC and the UE security capability sent back by the mobility management entity is consistent with the UE security capability carried in the attach request message sent by the UE ; and if the second hash value is consistent with the first hash value, the second NAS-MAC is consistent with the first NAS-MAC and the UE security capability sent back by the mobility management entity is consistent with the UE security capability carried in the attach request message sent by the UE, sending (S35), by the UE, a NAS security mode complete message to the mobility management entity. <EOS>