Provided are a method and device for reporting a capacity, a method and device for key agreement, a terminal and a communication device and system. The terminal sends anti-pseudo base station capacity indication information to the communication device, and the anti-pseudo base station capacity indication information can indicate an anti-pseudo base station capacity of the terminal to the communication device. The communication device can determine the anti-pseudo base station capacity of the terminal after acquiring the anti-pseudo base station capacity indication information sent by the terminal, and perform an authentication and key agreement process matching the anti-pseudo base station capacity of the terminal and an anti-pseudo base station capacity of a target base station.