Continual access to precise information about the land use/land cover (LULC) changes of the Earth’s surface is extremely important for any sustainable development program in which LULC serves as one of the major input criteria. In this study, a supervised classification was applied to three Landsat images collected in 1986, 1998and 2018, providing mangrove forests change data in the coastal area of the Bushehr province. The supervised classification results were further improved by employing image enhancement and visual interpretation. Visual interpretation was not only useful in increasing the classification accuracy of the Landsat images, but also in identifying the mangrove forest cover. Post-classification comparisons of the classified images of the mangrove forest area of the Assaluyeh habitat zone during a period from 1986 to 2018 indicated that the area of these lands had been increased by 68.94 hectares, with a percentage change of 43.85%, which was an increase of 1.41% per year. These changes in the Deir habitat zone showed that the area of the land covered by the mangrove forest was 5.25 hectares, with a percentage change of 0.87. In the Mela Ganza habitat zone, the area of the land covered by the mangrove forest was 26.82 hectares, with a percentage change of 6.33, which was an increase in the annual rate of 0.20.