Key generation method, master enodeb, secondary enodeb and user equipment<0}

The present invention relates to a key generation method, a master eNodeB, an secondary eNodeB and a user equipment. The key generation method comprises: determining a key parameter corresponding to a data radio bearer (DRB); sending the key parameter to a user equipment corresponding to the DRB, so that the user equipment generates a user plane key according to the key parameter and a basic key generated by the user equipment; receiving a basic key sent by the master eNodeB and generated by the master eNodeB; and according to the key parameter and the basic key generated by the master eNodeB, generating the user plane key.