The radiosonde vapor density is used as standards to analysis the accuracy of microwave radiometer and WRF vapor density data, both at 00:00UTC and 12:00UTC. As a whole, the vapor density profile of WRF seems closer to that of radiosonde comparing with the profile measuring by the groundbased microwave radiometer, but not including that near the surface, where it has a larger bias to sounding vapor density. It is also found that the maximum of vapor density deviation is in summer and the minimum is in winter. Besides, the vapor density of microwave radiometer has a small peak at about 3 km, because there exist clouds in the layer of 3 km to 5 km, which influences microwave radiometer’s vapor density retrieving. Using the WRF vapor density data at 06:00UTC and 18:00UTC as standards to assess the retrieving vapor density profile measured by the groundbased microwave radiometer, the similar result can be obtained.