The multipurpose maritime boundary between Latvia and Lithuania delimits the overlapping territorial seas, exclusive economic zones and continental shelves of the two States. The maritime boundary begins on the Baltic coast and extends west for 66 nautical miles before it terminates at a de facto tripoint with Sweden.

The maritime boundary agreement between Latvia and Lithuania has not yet entered into force as Latvia has thus far refused to officially ratify the document due to a dispute regarding the exploration and exploitation of a cross-boundary oil field located in the territorial seas of the two States.