Based on the precipitable water vapor calculated by radiosonde data (PWV_RS) at 00:00 UTC and 12:00 UTC in 2014 at Golmud station of Qaidam Basin, the accuracy of precipitable water vapor retrieved by GPS data (PWV_GPS) was tested. Meanwhile, the variation characteristics of PWV_GPS was analyzed at Golmud and Delingha stations in Qaidam Basin. The results show that daily variations of PWV_GPS and PWV_RS were consistent and the correlation coefficient between them was more than 0.9. The correlation was better in summer and autumn than in winter and spring, the correlation coefficient at 00:00 UTC was slightly higher than that at 12:00 UTC. At 00:00 UTC and 12:00 UTC, the RMSE of PWV_GPS was 1.8 and 2.4 mm, and the MRE was 0.2 and 0.4, and the BIAS was 4.2 and 4.3 mm, respectively. Monthly variation of PWV_GPS presented a single peak distribution, the maximum appeared in July and the minimum appeared in December. PWV_GPS was rich in summer and shortage in winter, and it was more in south and less in north. The diurnal variation of PWV_GPS ranged from 0.4 to 28 mm and the hourly PWV_GPS ranged from 6.9 to 7.3 mm.