Natural phenomena in the world, such as earthquakes and heavy rains, which are sometimes combined with wind storms, can cause landslides. These landslides in one area can damage several parts and cause significant damage to natural and human infrastructure. Landslides occur in almost all countries of the world and play an important role in the changing of the earth's surface. There are different geodetic and non-geodetic methods to measure the changes caused by this phenomenon. Geodetic methods are not suitable for preparing a landslide damage map due to their limitations such as high cost and time consuming. Therefore, we have to use non-geodetic methods. Nowadays, the use of remote sensing techniques has received much attention. Radar images have been proposed as a suitable tool for monitoring landslides due to their high spatial resolution, wide view, the possibility of capturing in any kind of weather conditions and during the night, the high frequency of spatial and temporal observations, and acceptable accuracy. In addition, there are various methods for extracting information from this type of data, most of which require large initial data, and time-consuming processing. But in this research, we are trying to produce a landslide damage map by using the least input data and in the shortest possible time (no need to spend time for downloading all the required data). Therefore, the method used in this research is the use of Sentinel-1A RADAR images and processing these images in the Google Earth Engine (GEE) processing platform. In this article, we will prepare landslide damage map by examining the changes in the backscattering coefficient image (σ° ) between before and after landslide RADAR images. In this research, by having two sets of images related to before and after the occurrence of the landslide in ASC and DSC pass mode, we can produce the Iratio image between the image before and after the landslide for ASC and DSC mode. After that, we can average between IratioASC and IratioDSC to produce the IratioAverage. After producing this image and removing areas that cause errors and ambiguity, such as seas and lakes, agricultural areas, deforested areas, etc. finally, by determining a suitable threshold, it is possible to detect landslide areas. In order to evaluate the accuracy, since the lack of ground data in the study area, the generated landslide map was compared with Sentinel-2 optical sensor images and the results showed a high agreement between these two data sets, and this shows the high accuracy of the proposed method.