Abstract: In order to study the land water cycle characteristics and drought disaster process and mechanism based on meteorological data in Huan County from 1958 to 2014, the seasonal and inter-annual variation trend, periodic mutation characteristics and impact factors of the 57 years were analyzed. The results showed that the inter- annual variability of evaporation was obvious, and the biggest evaporation of year and four seasons occurred in the late 1950s, the minimum evaporation appeared after 2000. The correlation analysis found that the evaporation capacity was positively correlated with average wind speed, average temperature and sunshine duration, but negatively correlated with relative humidity, precipitation. Analysis indicated that the major reason of evaporation decreasing in Huan County was the decrease of wind speed, and the second was the decrease of sunshine duration and the increase of precipitation.