Drought was one of the most important restricting factors to growth and development and yield formation for maize in Sichuan basin. To evaluate the severity of drought at different maize growth stages in Sichuan basin and provide a scientific basis for relevant departments to take effective hazard reduction measures, the drought level index was selected and drought distribution, such as drought intensity and frequency, in Sichuan basin was analyzed. The drought index was analyzed by using a maize water budget model including precipitation and crop water requirement, as variables. Drought index in Sichuan basin was classified by analysing the typical drought years and the corresponding drought data in history. The spatial drought distribution in different maize growth stages, drought intensity and frequency in recent 50 years was conducted by ArcGIS. The results showed that the maize drought occurred in high frequency between jointing stage and milk ripe stage. Sichuan basin was divided into three arid areas, and the south of Daba mountains, Fu river and Tuo river basin had the highest drought frequency through the whole growth season, generally greater than 50%.%干旱一直是制约四川盆地玉米生长发育和产量形成的主要因素.为评估四川盆地玉米生育期干旱状况,并为相关部门制定相应的防灾减灾措施提供科学依据,通过综合考虑降水量、同期作物需水量,利用基于水分亏缺原理的玉米干旱监测模型,对比分析典型年份干旱指数与相应干旱资料,确定了四川盆地玉米干旱等级指标,利用ArcGIS分析了近50a四川盆地玉米不同生育期、不同强度干旱发生频率的时空分布特征.结果表明:从不同生长阶段看,四川盆地玉米生育期干旱频率较高的时段主要为拔节-乳熟阶段,且发生面积最广.按空间分布特征把盆地划分为3大干旱区,其中大巴山以南、涪江及沱江流域在玉米全生育阶段出现干旱的频率最高,普遍都在50％以上.
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