Saint Martin Island or Coconut Island or Cinnamon Island is a small island about 9 km south-east of the Bay of Bengal from the Cox's Bazar-Teknaf Peninsula in Bangladesh. It is an island with an area of about 3 square kilometers. The southern part is called Chhera Island. St. Martin's Island is located about 6 km west of the northwest coast of Myanmar at the mouth of the Naf River and south of Shahpari Beach in the southernmost Teknaf Upazila of Bangladesh in the Bay of Bengal to the south. St. Martin's Island is about 6 kilometers long and about half a kilometer wide. Saint Martin Island is also known as Coconut Ginger or Coconut Island. Chera Dwip is situated in the southern part of the St. Martin Island and it is the ending point of Bangladesh.
Saint Martin Island consists of 9 areas at Deil para, Paschim para, Konar para, Majher para, Uttar para, Purbo para, Golachipa, Nazrul para and Dakshin para.
St. Martin's Island is around 510 kilometers from Dhaka, the capital city of Bangladesh, and Saint Martin Island, about 34 kilometers from Teknaf in Cox's Bazar district.