Snow is one of the main elements of hydrological cycle of the mountainous basins. In this study, snowmelt runoff was simulated using Snowmelt Runoff Model (SRM) in Bahar basin of Hamadan province, Iran. For simulation purposes, meteorological variables including temperature, precipitation and snow cover and also hydrological parameters and physiographic characteristics were used as inputs in this model. The Normalized Difference Snow Index (NDSI) was calculated from daily Moderate-resolution Imaging Spectroradiometer (MODIS) Level 1B data and was treshholded in Erdas Imagine 2014 software for discriminating snow from water surfaces, dense vegetation cover and shadow areas. The NDSI images showed strong correlations with MODIS snow cover products which indicate the appropriateness of the extracted NDSI maps in the study area. In this study, an interpolation method was used to calculate snow cover for cloudy days. Then Snow Cover Depletion Curves (SCDCs) were obtained using extracted snow cover maps and Digital Elevation Model (DEM) from 2013/12/22 to 2014/06/22. The percentage of daily snow cover which is an important input parameter in SRM model was achieved from the SCDCs over the related period. To run the SRM model, different parameters and variables were used including rainfall, air temperature, discharge, daily surface of snow, recession curve, snow and rain runoff coefficients, degree-day factor, critical temperature, rainfall-contributing area, lag time and physical parameters including elevation zones extracted from the DEM map. After defining all the parameters and variables, the SRM model was executed. According to the results, the runoff volume and average flow were simulated around 72/403 10 6 m 3 and 4.58 m 3 /s. The accuracy of the model was evaluated by comparing simulated and measured runoffs. The coefficient of determination (R 2 ), volume difference (D v ) and Criterion accuracy (D G ) were 0.80, 1.53% and 0.73, respectively which indicated that the runoff simulation has been successful in the study area. Based on the simulated hydrograph, the amount of runoff was constant in winter, but it reached its peak at the end of the winter which shows the importance of snow in flood prevention and control. Overall the results showed that the SRM can be effectively used to simulate snowmelt runoff which has an important role in water supply of the region. Keyword: MODIS, NDSI, Snow Cover, SRM, Hamedan