Abstract: In this paper, the models for calculating theoretical harvest area and meteorological disaster index were first developed by using method of linear moving average, regression analysis, information diffusion based on litchi production and meteorological data from 1990 to 2010 in Hainan province. The relative contribution of cold weather hazard to the reduction rate of litchi yield was separated from different weather disasters. Then, the model of yield risk assessment for litchi was developed and used in risk division based on considering the difference of production scale between towns. The results showed that higher risk regions of litchi yield were located in the north and middle of Hainan, and the risk rank of northwest was lower than the former. The lowest risk areas were mainly located in the south, southeast and southwest coastal towns. However, the middle, north and east where litchi was widely plant. In most parts, the high level of cold damage risk grade distributed in the middle and north and looked like a belt. The risk in Haikou, Qiongzhong and Wuzhishan were the highest，and in Chengmai was low; the lowest risk occurred in east, west and south coastal areas. The consistency is well shown between the division and fact of cold damage risk distribution for litchi, so the above results can be used to improve layout, prevent and reduce disaster as scientific foundation.

Key words: Theoretical harvest area, Reduction rate of yield, Litchi, Yield risk, Hainan