Abstract: In order to grasp the irrigation water requirement of citrus in western Hubei Province under the condition of climate change, formulate reasonable irrigation system and improve the utilization efficiency of water resources, based on the daily meteorological data of 9 meteorological stations in western Hubei Province from 1971 to 2019,this study used Penman-Monteith formula, single crop coefficient method and linear trend to analyze the temporal and spatial variation of citrus water requirement(ETc),effective rainfall(Pe),net irrigation water requirement(IR) and irrigation water requirement index(IRI) in different growth stages of Yichang City in recent 49 years.The results showed that the average values of ETc,Pe,IR and IRI in 9 citrus planting areas(Zigui, Xingshan, Yuan 'an, Yiling, Wufeng, Changyang, Zhijiang, Yidu and Dangyang County) in Yichang City were 728.6 mm, 414.96 mm, 313.64 mm and 0.43,respectively.The decreasing trend of ETc was mainly concentrated in Zigui and Dangyang County.The upward trend of Pe was mainly concentrated in Yidu, Zhijiang and Zigui County, and the Pe in the remaining areas showed a downward trend.The upward trend of IRI was mainly concentrated in Xingshan County, and the downward trend was mainly concentrated in Zigui County.In addition, the ETc of citrus in different growth stages showed the distribution characteristics of high in the east, low in the northwest and southwest, and gradually increased from west to east.The Pe had the distribution characteristics of low in the northeast and high in the southwest, and had a trend of gradually decreasing from southwest to northeast, which was opposite to the distribution characteristics of ETc.The IRI had the distribution characteristics of low in the southwest and high in the northeast, and there was a trend of gradual increase from southwest to northeast.In the future, under the influence of climate change, the citrus planting belt in western Hubei Province may gradually shift from northeast to southwest.