it’s a direct impact on the land water reserves inversion accuracy that GRACE(Gravity Recovery And Climate Experimen)time-varying gravity field stripe error. Weighted average filter algorithm is used to reduce this kind of error in this paper, and this algorithm is simple and effective, easy to implement by programming. the global continental water storage variation in May 2009 and drought in southwest China in 2010 was calculated using GRACE Level-2 RL05 gravity filed model published by CSR (Center for Space Research of Texas University in Austin), and the correlated errors are processed by weighted average filter. These results were compared with other methods. The comparison results show that weighted average filter is basically consistent with traditional algorithm, which verifies the effectiveness and reliability of the proposed algorithm.