The maritime boundary conflict between Indonesia and Singapore in the Singapore Strait has persisted as a strategic issue since the 1970s, driven by geographic proximity, Singapore’s land reclamation projects, and the incomplete delimitation of the boundary. This study aims to analyze the conflict resolution process using an international legal framework, particularly the United Nations Convention on the Law of the Sea (UNCLOS) 1982, alongside bilateral negotiation strategies adopted by both states. Utilizing a normative legal approach through legal document analysis and treaty review, the study reveals that the dispute was gradually resolved through three main agreements (1973, 2009, 2014), all of which adopted the equidistance principle. This resolution has promoted legal certainty, regional stability, and national sovereignty and serves as a model for peaceful maritime conflict resolution in Southeast Asia.