Malaysia and Thailand share two maritime boundaries, one which extends west into the Strait of Malacca and the other east into the Gulf of Thailand. The boundary in the Strait of Malacca extends for 109 nautical miles (M) in a southwesterly direction before ending at the defined tripoint with Indonesia.

In the Gulf of Thailand, only a short portion of the boundary has been established due to a disagreement over the delimitation of their continental shelf entitlements. The boundary extends northeastward from the land boundary terminus for 38 M. It ends at a Joint Development Area, which the Parties established in 1979 as a “temporary measure” while attempting to reach a delimitation agreement for the remainder of the continental shelf boundary. As of the 2024, no continental shelf boundary agreement has been reached, and the Joint Development Area remains in effect.