Abstract: To improve the low tracking accuracy of BeiDou B1C signal under low carrier to noise ratio(CNR), we proposed a B1C signal data/pilot joint tracking method based on extended Kalman filter. By constructing a data/pilot dual channel joint tracking model, the utilization ratio of B1C signal is increased. To undermine the tracking errors introduced by discriminator and loop filter in traditional tracking loop, extended Kalman filter is applied on the basis of the proposed joint tracking model, which further improves the tracking performance of tracking loop for low carrier to noise ratio signal. The experimental results demonstrate that compared with the conventional single-pilot channel tracking method, single-pilot channel extended Kalman tracking method and joint tracking method, the proposed method can effectively enhance the tracking accuracy under low CNR.