Abstract:The impacts of climate change on water consumption of dominant plants were evaluated in the mudstone area in southwestern Taiwan by using General Circulation Model. The results showed that the water consumption of the three dominant plants, eg. Bambusa stenostachya, Swietenia macrophylla and Cassia siamea, in the mudstone area increased significantly under simulated climate change. The Thorny bamboo (B. stenostachya) consumed more water than Honduras mahogany (S. macrophylla) and Siamese senna (C. siamea). Obviously, Thorny bamboo has important impact for soil water resources in the mudstone area during drought period.