A method and an apparatus for generating a security context are provided. The implementation of the method includes: receiving a first message carrying a network capability of a User Equipment (UE); and generating the security context according to the network capability of the UE carried in the first message if the network capability of the UE carried in the first message is inconsistent with the stored network capability of the UE. After the network capability of the UE changes, information carrying the network capability of the UE is sent to a network side, so as to inform the network side that the network capability of the UE changes; therefore the network side can obtain the network capability of the UE, generate the security context according to the changed network capability of the UE, and further trigger a Radio Resource Control (RRC) connection establishment process.