Abstract: There are three aspects in the study of GPS meteorology network in Wuhan region. The first is the comparison of the GPS precipitable water vapor between final ephemeris and ultra-rapid ephemeris which the relative coefficient is 99.97% and the root mean squares is 0.048 mm. It can be concluded that ultra-rapid ephemeris can be used to get the GPS precipitable water vapor for the real-time prediction. The second is the comparison of precipitable water vapor of GPS stations and it is acquired the distribution of water vapor in Wuhan region and the arrays from high to low are WHDH, WHJF, WHCD, WHXZ and WHHP. The change of GPS precipitable water vapor and rainfall in a rainfall process are compared and analyzed and the change of GPS precipitable water vapor can reflect and predict the process of rainfall.