The present invention discloses a method for configuring a Physical Downlink Control Channel (PDCCH), a base station and a UE, wherein the base station configures a component carrier or component carriers for monitoring the PDCCH for the UE and notifies the UE about information on the configured component carrier or component carriers so that the UE monitors the PDCCH only over the configured component carrier or component carriers. Stated otherwise, in this way, the UE will operate only over a necessary component carrier or component carriers without monitoring respective component carriers in an LTE-A system to thereby reduce the number of concurrently monitored component carriers, and in the case of nonconsecutive component carriers, also reduce the number of consequently enabled receivers and consequently the amount of consumed power of the UE for monitoring the PDCCH.