The “Sipadan and Ligitan” dispute was settled by the ICJ (2002), but its impact on basepoint for baseline and maritime delimitation on the Ambalat remains a contentious issue until now. Since the islands are used as basepoints by Malaysia that results in controversy between Indonesia and Malaysia. This essay will investigate the current situation over Ambalat regarding two basepoints islands for maintaining Equidistance Line in Disputed Area. It will discuss why Malaysia has no right to use the straight baseline or straight archipelagic baseline to connect the basepoints of Sipadan and Ligitan at Sabah and suggest measures to maintain equidistance line in Ambalat.

Maritime boundary issues have become a constraint in the relations between Indonesia and its neighboring countries, including Malaysia. One of the pending issues regarding the overlapping maritime boundary which is not yet to be resolved is the Ambalat area. The primary purpose of this research is to suggest possible senarioa to resolve the maritime delimitation dispute between Indonesia and Malaysia around Ambalt peacefully under international law. This article is prepared to explore all available ways for the peaceful settlement on Ambalat issue.The author will examine the diplomatic channel, ASEAN Way dispute settlement mechanism, adjudication process (litigation and arbitration), and dispute settlement under the UN Convention on the Law of the Sea. He will also epropose other innovative approach, such like Joint Development Zone. The result of such examination can be used as considerations for the way forward.