Abstract The Noel Besi-Citrana and Bijael Sunan-Oben border disputes between Indonesia and Timor-Leste generate legal uncertainty that undermines indigenous economic rights, including land tenure, customary livelihoods, and cross-border trade. This article aims to examine how the interaction of state law, customary law, and international norms affects the protection of these rights in contested borderlands. Employing normative legal research with a comparative case study design, the study analyzes domestic legislation, bilateral instruments, and documentary evidence of local economic practices. The findings indicate that jurisdictional vacuums and overlapping legal regimes exacerbate socio-economic marginalization and deter community-centered investment. Based on this analysis, the paper proposes a rights-based bilateral framework, explicit statutory recognition of indigenous economic entitlements, and the establishment of jointly governed Border Economic Zones that incorporate customary institutions and participatory governance mechanisms. The proposed measures are evaluated in terms of legal feasibility and potential socio-economic impact. By integrating legal pluralism with economic law, the study contributes policy-relevant models for reconciling territorial sovereignty with indigenous agency and sustainable development in disputed border regions. Abstrak Sengketa Noel Besi–Citrana dan Bijael Sunan-Oben di perbatasan Indonesia–Timor Leste menimbulkan ketidakpastian hukum yang mengancam hak ekonomi masyarakat adat termasuk akses atas tanah, mata pencaharian tradisional, dan perdagangan lintas batas. Tujuan penelitian ini adalah menganalisis bagaimana interaksi antara hukum negara, hukum adat, dan instrumen internasional mempengaruhi perlindungan hak ekonomi adat di kawasan sengketa. Penelitian ini menggunakan metode penelitian hukum normatif dengan pendekatan komparatif dan studi kasus, memeriksa peraturan nasional, perjanjian bilateral, dan bukti empiris praktik ekonomi lokal. Analisis menunjukkan bahwa kekosongan yuridis dan tumpang-tindih norma memperdalam marginalisasi ekonomi serta menghambat investasi komunitas. Untuk mengatasi hal tersebut diusulkan perjanjian bilateral berbasis hak, pengakuan eksplisit terhadap hak ekonomi adat, dan pembentukan Border Economic Zones/Kawasan Ekonomi Perbatasan (BEZ/KEP) yang dikelola bersama dengan mekanisme partisipatif dan penguatan peran lembaga adat. Studi ini berkontribusi pada sintesis pluralisme hukum dan hukum ekonomi untuk kebijakan perbatasan yang pro-komunitas.