Abstract: Bangladesh is an important joint along the Silk Road in the 21st century.The mangroves are widely distributed in the coastal zone, especially in the Sundarbans in the southwest.This study is based on the data of remote sensing images in 1990, 1996, 2000, 2005, 2010 and 2016, six period Landsat TM/OLI moderate resolution satellite was carried out based on the SVM method of Bangladesh coastal mangrove remote monitoring, applying 8 m spatial resolution GF1-PMS1 satellite remote sensing data in the test, given 6 times in Bangladesh coastal mangrove space the distribution, analyzes the evolution trend of mangrove 30 a.The results showed that:1) in the past 30 years, the area of mangrove forest in coastal area of Bangladesh showed a decreasing trend as a whole, with an area of 468218.932 hm² in 1990 and 17077.898 hm² in 2016; 2) the western part of the reduction, the central increase in the situation, nearly 30 a Eastern Chittagong area mangrove area decreased by 45.7%, the western Khulna area mangrove reduced by 2632.007 hm², but only 0.64% of the total area, the central Barisal area Mangrove area increased by 3108.604 hm²; 3) reduced area of mangrove area in the eastern Chittagong area is mainly located along the coast of Noakhali and along the zorarganj, mainly due to the establishment of shrimp ponds; the area of the subtropical forest is mainly distributed in the estuary of the Sundarbans, near the coast, the main reason for the reduction is the establishment of the shrimp and the human activities convert the mangrove forest into other types land; the central mangrove area distributed in the Barisal is mainly increase, the main reason is the natural growth and plants.