Based on the analysis of the characteristics of atmospheric water vapor calculation scheme processed by GAMIT software,the results generated by two kinds of different calculation schemes are comparatively analyzed by using the ground-based GPS data of 6 meteorological stations in Yunnan province.The analysis and accuracy test are conducted by comparison with the radiosonde data.The results show that the two calculation schemes are quite different in the retrieved water vapor results.The precision of GPS water vapor is obviously improved after adopting the local model.The water vapor values derived from GPS are roughly in agreement with the radiosonde observations with a mean-root-square error less than 2mm,and the changing trends of them are basically the same.The study revealed that the retrieved water vapor generated by the ground-based GPS calculation scheme in the local model can be used in research business.