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The Zagros Mountains are one of the key water sources for Iran and recession of the snow line would have an impact on regional water resources. In this study, we used Moderate Resolution Imaging Spectro radiometer (MODIS) data obtained from 2000 to 2016 to investigate the upward retreat of the Temporary Snow Line Elevation (TSLE) for the months with the greatest snowfall and highest snow lines (December, January, and February) in the Oshtorankooh region. In addition, to gain a better insight into the impact of recent climate change on the snow cover in Oshtorankooh and its TSLE variations, the Mann-Kendall and TSA non-parametric tests were used for the time period 2000-2016. The results showed an upward retreat of the TSLE. The ground surface temperature observations analyzed using the MODIS data show a temperature increase of 0.52-0.99 degrees C (Aqua MODIS) and 0.82-1.12 degrees C (Terra MODIS) in the same time period. According to the Mann-Kendall and TSA methods, climatic parameters have changed during recent years in most of the studied stations and climate change is responsible for Oshtorankooh TSLE variation, so that the TSLE during the studied statistical period demonstrated an upward movement in four orientations (North, South, East, West).The largest variation between December and the other months (January and February) was observed between 2004 and 2016 247.18 km(2), 76.05 km(2), and 249.64 km(2), respectively.