Аннотация:In the last 60 years, huge-scale irrigation project has been carried out and this project has occurred serious water scarcity in the Aral Sea Basin. The Aral Sea has shrunk to 10% of 1960's level and a lot of people are suffering from serious water scarcity. To solve the problem, sustainable irrigation plan is required. For the plan, quantity of water resources and the impact of global warming must be simulated. In this study, annual water and heat balance in the Aral Sea Basin is analyzed from 1961 to 2003 by SiBUC. SiBUC is one of the land surface models which can analyze water for irrigation in physical way. Water balance in this basin is reproduced in the past and the impacts of expanding irrigated area to water balance in this basin are analyzed.