The objectives of this study were to assess land suitability and to monitor the spatial and temporal changes in land use types (LUTs) by using GIS. The study was conducted in an irrigated area of 920 ha, located in the East Mediterranean region of Turkey. Archived data of LUTs were utilized. Data analysis was conducted by using ArcInfo and ArcView GIS softwares. The land characteristics were compared with land requirements of present LUTs by taking into account the land evaluation results. Three major soil series and twelve different LUTs were identified. Corn and citrus were the most planted LUTs in the assessment period. Generated maps demonstrated how LUTs changed spatially and temporally. Most LUTs were clustered in certain areas indicating that farmer's selection of LUTs was affected by their habits and neighbor's behavior. Land suitability assessment results indicated that Canakci and Mursel soil series were found to be highly suitable for all LUTs while Arikli soil series was determined to be moderately suitable citrus, vegetables and watermelon. Citrus plantation maps overlaid on soil series maps demonstrated that the citrus has not been planted completely on suitable areas. Land suitability assessment showed that citrus plantation in Arikli series would result in 40% yield loss and 58% of land is not used at its potential.