Selecting three calculation methods of atmospheric precipitable water: groundbased GPS remote sensing water vapor, radiosonde data inversion, and empirical formula methods, taking Weining as an example, the similarities and differences of three methods in the Wumeng Mountain area are analyzed. It is concluded that selecting the radiosonde inversion value as the baseline, the results of GPS remote sensing and empirical formulas are bigger than the baseline; there is a good correlation among three values, especially between GPS remote sensing and radiosonde inversion; the minimum average absolute error value is 3.5 mm and the root mean square error is 4.14 mm. The empirical formulas of the weighted mean tropospheric temperature for the Wumeng mountain area is established, with the average error between empirical formulas and baseline is 1.1 K. The empirical formulas of weighted average〖WTBX〗 〖WTBZ〗air temperature have little influence on the atmospheric precipitable water. The GPS inversion accuracy of water vapor is higher when there is precipitation and the quasistationary front over Kunming between November and April, with the average absolute error being only 1 mm. The average absolute error between radiosonde inversion and experience calculation is 0.74 mm from May to October.