Abstract: Based on the ground observation data from 82 meteorological stations during 1961-2010 and longterm tea experimental observations data, using some methods recommended by Food and Agriculture Organization, the water requirement were calculated in different growing seasons for tea plants in Guizhou. The temporal-spatial variation and the trend of water requirement for tea plants were evaluated by the methods of statistics and ArcGIS in order to assess the impact of climate change on tea plants. The results indicates that, the water requirement of tea plants in Guizhou has significant differences in different growing seasons in nearly fifty years, the summer tea water requirement accounts for the most, followed by autumn tea; the spatial distribution of summer tea water requirement is similar to that of the autumn tea, which shows a type of "northwest low southeast high"; on the contrary, the water requirement shows a type of "northeast low southwest high" for spring tea and during wintering periods. The averaged water requirement shows a decreasing trend in all of the growing season; the annual climate tendency rate is - 1.6, -4.8, -1.2, -0.3 mm per ten years for spring tea, summer tea, autumn tea, and winter tea, respectively. The water requirement difference of spring tea and winter tea in different regions are decreasing while the water requirement differ? ence of summer tea and autumn tea are increasing over the past five decades.