Land desertification is one of the most serious ecological problems in the world. Detection and attribution of land desertification has become a research focus in recent years. The social and economic status is influenced by desertification more significantly in the developed coastal areas. Hainan Island is a typical coastal region with severe desertification in China. With the impact of topography, western Hainan Island is tropical semi-arid region with the average annual temperature (24.92℃) and annual precipitation (987.56mm) in 60 years. The distribution of precipitation in a year is non-uniformity, mainly distributed in second half of the year. Annual evaporation of the region is far larger than the annual rainfall. Therefore,the incoordination of water and heat condition causes severe land desertification in west coastal region of Hainan Island. In this study, we collect Landsat-TM imageug (9 periods), MODIS data (322 periods) and meteorological data of western Hainan Island, and extract land desertification information of study area based on difference of spectral characteristics. Then we use multiple methods and RS/GIS techniques, to analyze the spatial-temporal patterns of land desertification and their relationship to climate variations in western Hainan Island during 1989 ~2010. The main conclusions are as follows:(1) The non-desertification area has been sharply increasing at a rate of 9.2km~2/a during 1989 ~ 2010. The decreasing of mild desertification area played an important role in the desertification control with 193.57km~2 (64.2%) decreased, and the severe desertification area showed the most abrupt decline (24.26km~2, 91.0%). (2) Based on a transition matrix of desertification land in western Hainan Island, the desertification area decreased by 174.04km~2 consisting mainly of moderate desertification area (67.67%). During the 20 years' period, the desertification land types that had changed were non-desertification land (1.59%),mild desertification land (94.67%), moderate desertification land (98.02%) and severe desertification land (99.46%). (3) Desertification lands are mainly distributed near the sea and have a low vegetation cover, which could be easily influenced by frequent human activities. In the recent 14 years, desertification has been improved greatly with the increasing vegetation cover in the northern and central parts of the western coastal areas. (4) Correlation analysis between land desertification and climate factors (precipitation and temperature) indicates that non-desertification areas are significantly correlated with average annual temperature and precipitation with correlation coefficients of 0.82 (p<0.01) and 0.73 (p<0.05), respectively. Temperature and precipitation are both important influencing factors for land desertification in western Hainan Island, with precipitation being a leading factor, although human activity as another important factor cannot be neglected.