Wetlands are among the areas on the surface of the earth whose life and dynamics depend on the presence of water, this dependence is so great that they react to fluctuations and changes in water levels in the shortest possible time. The aim is to investigate and reveal changes in NDVI and NDWI in Shadegan Wetland using remote sensing. In this regard, using Landsat images in the period (1972-2020) in June, we investigated and revealed changes (decrease and increase) in NDVI and NDWI and estimated the water level in the wetland catchment area in hectares. After obtaining images from the site https://glovis.usgs.gov, the images were processed and the water cover area was calculated using ENVI and GIS software. In one year, we witnessed an increase in the wetland water level, this increase was repeated only in the next two or three years, and after that, we were faced with a decrease in the wetland water level. In 1975 to 1978, more than fifty percent of the wetland surface was covered by water, but in 1980, the water surface coverage decreased to 15 percent. The decrease and increase in the wetland water level changes in the following year, and its changes from year to year are large. Based on the results obtained, it was determined that in the catchment area of the wetland, the water available in this wetland fluctuates greatly. In the 23-year period under study, the water available in this section is less than 50 percent. The water availability in the wetland has an uncertain trend that does not follow a specific order. Since water is considered the most important life-giving element in wetlands, this high irregularity or severe fluctuation in water availability can be considered a serious threat to the life of the Shadegan wetland ecosystem.