Sundarban Mangrove Forest in Bangladesh is playing a significant role in local and national economy and is providing protection to the coastline as well as to the indigenous people. During the past decades and also in recent time this forest was heavily disturbed by human intervention in many aspects. As a consequence the resources of the forest are fragmenting, shrinking and declining, which in turn leads to an increasing failure of satisfying increasing demands both at local and national levels. Therefore accurate and continuously updated spatial information is needed for optimizing forest management and environmental planning on both levels to support the fulfillment of urgent needs of sustainability of the development of the forest ecosystems. The present study is an investigation examining the underlying causes of deforestation, forest cover change and its environmental impact. Remarkable changes of the forest cover have been occurred from 1997 to 2006. In the present study, dense forest cover have been changed drastically and converted into light forest in 2006. The total 1.17% forest cover area is reduced.