: Today, due to population growth, inadequate management practices and lack of oversight of land degradation processes have caused many watersheds to be severely degraded, leading to increased runoff and sediment. Therefore, its role in sediment production and waste management helps managers to plan for conservation. In this study, the aim of the study was to investigate the effect of land use change on surface water fluctuations in the Doiraj watershed. We used Geographic Information Systems and Remote Sensing which were accepted in many researches in order to prepare land use maps. Landsat satellite imagery was used for three periods of 1995, 2006, and 2015, it was found that the major changes occurred with decreasing forest and rangelang levels and increasing land barren. For modeling rainfall-runoff, a SWAT computer model was used. The main inputs of the model, which include meteorological data, a basin's elevational digital model map, a soil map and land use map, are entered into the model. The model was implemented according to the curve number method, Then, using the SWAT_CUP model, the performance of the model increased with entering the observation data of the discharge from the basin and performing the calibration steps during the period from 1996 to 2008. And then the validation step from 2009 to 2012 confirmed the model's ability to simulate rainfall-runoff and its use for study purposes. The performance of the model was evaluated using statistics, NS, R2, P_FACTOR and R_FACTOR. After calibration and validation, the values of these coefficients were 0.58, 0.60, 0.81, 0.87 for the calibration period and 0.56, 0.57, 0.81 and 89 for the validation period of the model, respectively was obtained. The results of calibration and validation showed that for the Doiraj study basin, despite the low number of rainfall measurement stations and the low number of hydrometric stations, it is an appropriate test for the analysis and evaluation of runoff. Annual runoff estimation indicated that the change in utilization from 1995 to 2015 increased the outflow runoff from the basin, so that the average total from 3.91 m3 / s (landuse 1995) to 4.44 m3 / s (landuse 2006) it is arrived. Most of the disagreements are about landuse2015, so that the runoff is 5.85 cubic meters per second. In this study, the CN value for landuse 1995, 2006, 2015 is 67.51, 71.4, 72.78. A monthly discharge analysis indicated that CN increase would increase surface runoff in high rainfall season and reduce base flow in the warm seasons of the year. Keywords : Land Use Change, SWAT, SWAT_CUP, Doiraj Watershed, Surface Runoff, Geographic Information System and Remote Sensing, calibration, validation