Differences between the littoral states regarding the status of the Malacca Strait result in disharmony and inconsistencies in handling spatial planning and preventing marine pollution in the strait. International cooperation with user countries carried out so far is also not optimal due to conflict of interests. Using a normative juridical approach and secondary data of the provisions of United Nations Convention on the Law of the Sea (UNCLOS) 1982 and the Declaration of the Three Strait States, the Malacca Strait is under the sovereignty of the littoral states and used for international navigation with transiting passage. Spatial planning in the Malacca Strait, which results in overlapping uses for cross-fishing vessels, conservation, and traditional fishing, cannot be performed because the problem of maritime boundary determination has not been resolved by the littoral states. Tripartite cooperation needs to continue to be built through agreements that not only bind the littoral states but also the user states.