Abstract: Based on the data of MWP967KV type Ground-Based Microwave Radiometer and L-band sounding,we use statistical methods like mean deviation,correlation analysis and regression analysis to evaluate the differences between Microwave Radiometer and L-band sounding in precipitation and no precipitation conditions,so as to understand the performance of Ground-Based Microwave Radiometer.The research reveals that:(1) an obvious linear correlation exists between the temperature,relative humidity and water-vapor density detected by Ground-Based Microwave Radiometer and sounding;comparatively,the character of relative humidity is dispersion;(2) in condition of non-hydrometeor,the average error of relative humidity and water-vapor density is small;in condition of hydrometeor the root-mean-square error of temperature and relative humidity is large;in lower atmosphere and condition of non-hydrometeor,the average error of temperature is small,the root-mean-square error of water-vapor density is large;in middle and higher atmosphere and condition of hydrometeor,the average error of temperature is small,the root-mean-square error of water-vapor density is large;(3) the temperature and water-vapor density show an obvious positive correlation;in condition of hydrometeor the relative humidity shows an obvious positive correlation of 0-2km and an obvious negative correlation of 9.25-10km;in condition of non-hydrometeor it shows an obvious positive correlation of 0-8km.Generally speaking,Ground-Based Microwave Radiometer makes up for the shortage of sounding,the reliability of relative humidity needs to be further improved,and precipitation has a greater impact on Ground-Based Microwave Radiometer.