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With a total population of 278000, Sandwip has long been facing severe land erosion and accretion problems because of its geographical setting in the coastal area of Bangladesh. This research aimed to assess the erosion and accretion status along with the shoreline movement of this island based on multi temporal Landsat imagery and hydrological data from 1974 to 2014. The results revealed that water discharge and water level data are positively correlated with erosion and negatively correlated with accretion data. The results also indicate that the island has lost around 90 km2 of its stable and gained around 17 km2 of new land. The erosion activity is mostly happening in the northwestern, western, and southern banks whereas accretion has been occurring at a slower rate in the northern and eastern banks of the island. Because of this dynamic erosionaccretion activity the shoreline of the island has been moving towards the northeast side. This 40 years’ data analysis solemnly affirms that maximum shoreline movement towards the land was 4004 meter in the southern bank with annual rate of approximately 100 m per year. At the same time interval, maximum seaward movement of the shoreline was observed in the northeastern portion (NSM> 2247 m) at a maximum net rate of around 56 m per year (EPR= 55.85 m per year). Because of this idiosyncratic characteristic Sandwip’s total land area was reduced to 73 km2 during 1974 and 2014.