In this study, the potential areas to cultivate rice in Lorestan province were studied using GIS. First, environmental conditions, especially climatic conditions, affecting rice CULTIVATION were investigated to determine climatic thresholds. After gathering basic climatic data and statistical analysis, required digital maps including topography map, drainage network, soil resources were provided in 1: 250000 scale, and afterwards, all related attributed data was fed into GIS database. Then, using GIS spatial functions isomaps, such as slope gradient map, and isohyets map, were prepared. Then, the data was classified and weighed and the potential map was produced. The produced map, existing land use map and drainage map were jointly used to identify the areas that have economical benefits to be changed from current land use to rice CULTIVATION. The results indicated that about 28000 square kilometers that is 27 percent, of the province had high potentiality for rice CULTIVATION.