The influence of multipath effect on pseudo-range measurement is always an important constraint for integrity monitoring of satellite system,and carrier phase smoothing code pseudo-range method can restrain the influence effectively.Considering that the pseudo-range measurement of BeiDou System (BDS) is easily affected by the multipath effect,we proposed an improved Hatch filter to solve the problem.The relational expression of the filter parameter θ with pseudo-range variance was established,and the new filter parameter was selected based on principle of minimum variance.The results show that the new method can improve the precision of pseudo-range measurement,and decrease the bias and fluctuation range of B-value.This method can improve the capability of multi-reference consistency check.