A once—in—a—century drought occurred in 2009/2010 over Yunnan province, which seriously impacted people's lives. Based on the moderate resolution imaging spectroradiometer (MODIS) data from November 2009 to April 2010 provided by National Aeronautics and Space Administration (NASA), the temperature vegetation drought index (TVDI) was constructed to detect drought over Yunnan in 2009/2010. After comparing the TVDI with the observed soil moisture of Kunming, Zhaotong and Jiangcheng, the spatiotemporal evolution of drought in 2009/2010 was revealed. The monitored results show that after enter ed the dry season, drought occurred in Yunnan with different level. The most severe drought conditions appeared in February and March, 2010 in which the medium drought area reached more than 50% and the severe drought area reached about 27% of the total area. Severe drought area was mainly distributed over the southern and eastern Yunnan. Only Diqing and Nujiang Autonomous Prefectures located in northwestern Yunnan were relatively wet.