Based on meteorological observations such as pan evaporation, temperature, sunshine hours,wind speed, humidity during 1956-2005 in Shuozhou ofShanxiProvince, the annua,l monthly and seasonalvariation ofevaporation in Shuozhouwas analyzed in detai,l and the influence factors of evaporation were also discussed. Results show that the evaporation presented an obvious downward trend in recent50 years in Shouzhou, especially in spring and summer, and decreasing trendwasmost remarkable inMay; Therewas obviously positive correlation between evaporation and sunshine hours, mean wind speed, mean temperature daily range, but negative correlation between evaporation and relative humidity, vapor pressure, which indicated that sunshine hours, mean wind speed, mean temperature daily range, relative humidity and vaporpressureweremain factors resulted in evaporation decrease in Shouzhou of Shanxi Province.