Saint Martin Island (Bengali: সেন্টমার্টিন দ্বীপ, romanized: Sēnṭmārṭin Dbīp) is a small coral island in the north-eastern part of the Bay of Bengal, about 9 km south of the tip of the Cox's Bazar-Teknaf peninsula, and forming the southernmost part of Bangladesh.

It is about 8 kilometres (5 miles) west of the northwest coast of Myanmar, at the mouth of the Naf River.

Between October and April, the fishermen from neighbouring areas bring their caught fish to the island's temporary wholesale market.

During the rainy season, because of the dangerous conditions on the Bay of Bengal, the inhabitants are unable to travel to mainland (Teknaf), leaving the island isolated.

[11][12] Marine sponges and their associated microbes produce an enormous array of antitumor, antiviral, anti-inflammatory, immunosuppressive, antibiotic and other bioactive molecules.

[10][15][16] Fish (Labeo rohita) fed with extracellular products of Bacillus subtilis strains WS1A and YBS29 develop complete disease resistance.

[14] The only way to reach Saint Martin Island is by water transportation: boats and ships (mostly for tourists) from Cox Bazar and Teknaf.

Most hotels run generators until 11 PM which is not allowed afterward, so they rely on solar power, which is popular throughout the island.

A number of efforts have been proposed to preserve the several endangered species of turtles that nest on the island, as well as the corals, some of which are found only on Narikel Jinjira.

Its north-eastern side and southern-most part including Chhera Dwip is surrounded by sparse coral colonies.

Fishing is one of largest professional activities of St. Martin's Island's 5,500 residents; however, territorial disputes between Myanmar and Bangladesh have resulted in a state of tension between the countries that can erupt into violence, often targeting unarmed Bangladeshi fishermen.

Below is a brief summary of shooting incidents against St. Martin's fishermen: The best weather is usually between November and February; this is the major tourist season.