An embodiment of the present invention discloses a power control method, including: obtaining, by a UE, configuration information, where the configuration information includes a configuration parameter of at least one Scell configured by a base station for the UE; setting, by the UE, an initial power adjustment value of the Scell according to the configuration parameter of the Scell in the configuration information; and controlling, by the UE, transmit power on the Scell according to the set initial power adjustment value of the Scell. Correspondingly, an embodiment of the present invention further discloses an activation management method, a UE, and a base station. By using the present invention, transmit power of a UE on an Scell can be accurately controlled, thereby ensuring accuracy of data transmission.