Based on the daily meteorological data of 124 agricultural meteorological sites during 1977-2010 in Yunnan Province, using recommended PenmanMonteith formula by FAO, water requirement and irrigation requirement index in the growth period of fluecured tobacco were calculated to analyze their spatial and temporal characteristics and change patterns. The results showed that water requirements of fluecured tobacco in root extending, vigorous, mature periods and field growth period during 1977-2010 were 76.73-174.73, 247.50-386.64, 180.28-258.14 and 528.18-764.08 mm, respectively, and the water requirement of vigorous period was the highest. The average irrigation demand index of each period was -0.02, 0.38, 0.17 and 0.26, respectively. Effective precipitation could meet the demand of fluecured tobacco in root extending period. Water requirement of fluecured tobacco in Yunnan Province decreased annually, and the rates of water requirement under the climate change trend in the four periods abovementioned were -12.42, -21.46, -7.17 and -47.15 mm·(10 a)^-1, respectively. The smallest irrigation demand index was observed in Dehong, and the largest in Diqing. The irrigation demand indexes of Dehong, Xishuangbanna and Puer regions were negative in fluecured tobacco field growth period. The reference crop evapotranspiration, water requirement and effective precipitation decreased, but the irrigation requirement and irrigation requirement index increased with the increase of latitude. The effective precipitation decreased, but the irrigation requirement and irrigation requirement index increased with the increase of altitude.