A method and apparatus are disclosed determine a CFI value in a wireless communication system. In one embodiment, the method comprises configuring system devices, such as a UE or an eNB, with a plurality of component carriers for carrier aggregation. Furthermore, the method comprises receiving PDSCH on a first component carrier. The method also comprises transmitting a corresponding PDCCH on a second component carrier. In addition, the method comprises using a RRC signal to configure a CFI with an initial configured value. The method further comprises setting the CFI so that the CFI could be used to determine a starting point of the PDSCH.