Assam is one of the most forested states in India. These forests support a large number of important species and endemics and have great significance for global efforts in biodiversity conservation. Therefore the need for assessment and monitoring forest cover change has become essential in managing natural resources and observing environmental changes. In this paper an attempt has been made to detect the landuse/landcover changes before and after institutional change (1989-2011) of Amchang Wildlife Sanctuary, Assam. The study was carried out through Remote Sensing and GIS techniques using SOI toposheets and Landsat imagery of 1989 and 2011. The present study has brought out that the water bodies and moderately dense forests decreased sharply during the 22 years period by 17.64% and 50.35% of hectares. On the other hand the dense forest and open forest area increased by 13.35 % and 2% of hectares. Most of the dense forest and moderately dense forest area has converted to open forest and non-forest area. Non-forest area like settlement area has increased to 49.96% of hectares during the 22 years period.