Abstract: As a key technique of the next generation wireless communication systems, coordinated multiple point (CoMP) can efficiently eliminate inter-cell interference and enhance the performance of cell-edge UEs. In frequency-division-duplexing (FDD) systems, its performance heavily depends on the accuracy of the channel state information (CSI) obtained by base stations (BSs) via limited feedback. However, the same accuracy of CSI in all cooperative BSs results in the problem that the feedback overhead scales linearly as the number of cooperative BSs. Focusing on how to get tradeoff between performance gain and feedback overhead, this paper proposes an adaptive Precoding Matrix Index (PMI) feedback scheme for CoMP joint transmission. According to the differences between channel qualities indicators (CQIs) of downlink links associated with different cooperative BSs, UE can allocate different number of bits to PMIs of different-strength links. Specifically, more bits are assigned to the PMI of downlink channel with higher CQI and vice versa. Systmatic simulation result shows that this method can dramatically reduce feedback headover while maintaining a majority of the performance comparing to the traditional feedback scheme.