A method and apparatus for aperiodic CQI/PMI/RI reports in a wireless communication system is disclosed. The wireless communication system supports carrier aggregation that enables a user equipment of the wireless communication system to perform transmission and/or reception using multiple component carriers. The method includes reporting CQI/PMI/RI for multiple component carriers. When the user equipment needs to report CQI/PMI/RI for a deactivated component carriers, a special value may be used to signal the condition. Alternatively, the user equipment indicates with the reported CQI/PMI/RI which component carriers are measured.