Soil moisture is a key parameter of the ecosystem. Real-time and effective monitoring of soil moisture helps to enhance our understanding of regional climate and environmental change. MOD11A2 and MOD13A2 of MODIS synthetic products in DOY (Day of Year) 177-225 between 2000 and 2014 was used to obtain the Land Surface Temperature and Normalized Difference Vegetation Index, and the status of soil moisture on the Qiangtang Plateau covering the summer from 2000 to 2014 was evaluated based on the method of Temperature Vegetation Dryness Index (TVDI). The spatial distribution of soil moisture in the summer of 2014 was analyzed as an example, and the dynamic changes of soil moisture during 2000-2014 were further discussed. The results show that: (1) The soil moisture of the Qiangtang Plateau in 2014 was generally humid in the southeastern part, while it was arid in the northwestern part. Soil moisture gradually reduced from east to west, dry and wet conditions were found alternately between south and north. The percentages of areas of dry soil, partially dry soil, normal humidity soil, partially wet soil, and wet soil were 3.84%, 27.17%, 37.64%, 29.63%, and 1.72%, respectively in 2014. (2) In July and August from 2000 to 2014, soil moisture in the northern and central parts of the plateau showed a significant trend of getting dry, while that in the southern part showed a trend of getting wet with little significance. The proportion of area of dry soil and wet soil in the study area was the smallest and had little fluctuation from 2000 to 2014, while that of partially dry soil, normal humidity soil, partially wet soil had different fluctuations. (3) Precipitation was an important factor affecting TVDI, and had the certain hysteresis, while the impact of temperature was relatively small.