Abstract: Since the successful cultivation of the Brazilian Upland Rice (IAPAR-9) in Guangxi, it is decided to be the first choice to widely promote the farming at present, because of its characteristics of wide adaptation, strong resistance to virus and adversity, high yield and high rice quality. In order to reasonably use the climate resources, to get high and steady yield and popularize the Brazilian Upland Rice, and to avoid losing because of blindfold development in unfit region, it is necessary to study on the zoning of fitting region for Brazilian Upland Rice planting in Guangxi by using GIS technology and small grid calculating method of the climate resources, which will provide scientific basis on reasonable distribution of developing Brazilian Upland Rice in Guangxi.According to the request for climate conditions of Brazilian Upland Rice during its growth and development, considering the several years experimental results of cultivation in Guangxi, it is analyzed and the key climate factor and the climatic zoning index which have effects on the growth of Brazilian Upland Rice in Guangxi are determined. Using the climatic data from 1961 to 2000 and geographical information data of 86 weather stations in Guangxi, space calculating models for the zoning index are founded by the regress method of mathematical statistic. In the model, the geographical factors including the longitude, latitude and height above sea level are independent variables and the climatic zoning index is dependent variable. Based on the GIS technology, and the use of the basic Guangxi geographic data on the scale of 1 to 250000, calculation of small gridding and correction of error are operated for those zoning index. The actual distribution of the climatic zoning index is worked out on a small grid of l km×l km, which gives different values under different geographical conditions.Using the function of spatial analyses and multi-overlapping method of GIS and according to the zoning index on all kinds of the dividing grades in climatic division, grid data of the zoning index are calculated in the climate zone by the method of scoring to sort out the kinds. Then the climatic zoning of fitting region for Brazilian Upland Rice planting in Guangxi are done. It is the distributing result to find out suitable and unsuitable planting regions for Brazilian Upland Rice of double crop, ratooning rice, single season rice in Guangxi. The map of climatic division planting Brazilian Upland Rice in Guangxi can be drawn by GIS, and the assessment and corresponding suggestions for results of the different planting region are put forward.