Tree felling in tropical forests is done for the purpose of slashand- burn agriculture after which a forest may revive back to its natural condition or may lead to degraded land. The present study was carried out to assess the deforestation rates due to slashand- burn agriculture using temporal remote sensing data. The design framework is motivated by spatial analysis of deforestation and slash-and-burn driven by indiscriminate tropical forest patch removal. In the current study it is revealed that the area under slash-and-burn increased by many folds during the last two decades (0.83% in 1991 and 5.15% in 2010). During the decades again a large chunk of forests estimated about 2,585 sq km were lost due to burning of biomass for shifting cultivation. The rate of forest degradation in all the three districts of Garo hills are identical in both the decades, but due to the efforts made by agencies there was gain of forest areas in one of the Garo hills districts in the later decade. There is no doubt about the increase of CO2 and other greenhouse gases due to burning of the tropical biomass in the Garo hills region of India. There are plenty of scopes left for undertaking scientific research in this field.