ABSTRAK Wilayah perbatasan darat Indonesia - Malaysia di Kalimantan Barat merupakan area rawan penyelundupan narkoba akibat kondisi geografis yang kompleks dan tingginya aktivitas lintas batas. Maraknya drugs trafficking di kawasan ini telah menjadi ancaman serius bagi keamanan dan kesehatan masyarakat kedua negara. Oleh karena itu, kerja sama bilateral antara Indonesia dan Malaysia menjadi sangat penting. Kedua negara memiliki kepentingan yang sama dalam mengatasi permasalahan ini, sehingga kolaborasi dalam bentuk pertukaran informasi, patroli bersama, dan peningkatan kapasitas aparat penegak hukum sangat diperlukan. Selain itu, kerja sama ini juga dapat mencakup upaya pencegahan, rehabilitasi pengguna narkoba, dan edukasi masyarakat tentang bahaya narkoba. Metode penelitian yang digunakan adalah normatif-preskriptif dengan pendekatan kualitatif, data yang dikumpulkan diperoleh dengan teknik wawancara, bahan pustaka, konvensi internasional, dokumen hukum, serta laporan instansi terkait. Penulis mewawancarai beberapa narasumber yaitu, ibu AKBP Sri Sulasmini, S.H., M.H. Kepala Bagian Bin Ops Ditnarkoba POLDA Kalimantan Barat, bapak AKBP Jajang S.Kom Kasubdit 2 Ditresnarkoba POLDA Kalimantan Barat, bapak AIPDA Ryan Herman penyidik di BNNP Kalimantan Barat. Hasil penelitian menunjukkan bahwa implementasi hukum kerja sama Indonesia - Malaysia dalam menanggulangi peredaran narkotika di wilayah perbatasan darat Indonesia-Malaysia di Kalimantan Barat mencakup pertukaran intelijen, rapat tahunan, dan patroli perbatasan. Kendala utama meliputi luasnya wilayah perbatasan darat, sistem yang belum sepenuhnya berjalan, ketersediaan infrastruktur, keterbatasan sumber daya, dan modus perdagangan yang kompleks. Meski berhasil menangkap pelaku dan menyita narkotika, efektivitas kerja sama masih perlu ditingkatkan melalui harmonisasi kebijakan dan pemanfaatan teknologi. Kesimpulan dari penelitian ini menekankan pentingnya harmonisasi kebijakan, peningkatan kerja sama lintas instansi, dan optimalisasi teknologi untuk memperkuat penanggulangan drugs trafficking. Rekomendasi yang disarankan antara lain pembentukan sistem database terintegrasi, pelatihan khusus bagi aparat, serta pemanfaatan teknologi modern seperti drone untuk memperluas cakupan pengawasan tanpa terbatas oleh kendala luasnya wilayah perbatasan darat Indonesia dan Malaysia di Kalimantan Barat. Kata Kunci: Kerja sama bilateral, drugs trafficking, perbatasan Indonesia-Malaysia, penegakan hukum. "ƒ ABSTRACT The Indonesia-Malaysia land border area in West Kalimantan is prone to drugs trafficking due to its complex geography and high level of cross-border activity. The prevalence of drug trafficking in this region poses a serious threat to the security and health of both countries. Therefore, bilateral cooperation between Indonesia and Malaysia is very important. Both countries share the same interests in addressing this issue, so collaboration in the form of information exchange, joint patrols, and capacity building for law enforcement agencies is essential. Additionally, this cooperation can also include prevention efforts, rehabilitation of drug users, and public education about the dangers of drugs. The research method used is normative-prescriptive with a qualitative approach, and the data collected was obtained through interviews, literature, legal documents, international convention, and reports from relevant agencies. The author interviewed several sources, namely Mrs. AKBP Sri Sulasmini, S.H., M.H., Head of Operational Development at the West Kalimantan Regional Police Narcotics Directorate; Mr. AKBP Jajang S.Kom, Deputy Director 2 of the West Kalimantan Regional Police Narcotics Directorate; and Mr. AIPDA Ryan Herman, an investigator at the West Kalimantan National Narcotics Agency. The research findings indicate that the implementation of Indonesia-Malaysia cooperation in combating drug trafficking in the land border area of West Kalimantan includes intelligence sharing, annual meetings, and border patrols. The main obstacles include the vastness of the land border, a system that is not yet fully operational, the availability of infrastructure, limited resources, and complex trafficking methods. Although successful in apprehending perpetrators and seizing narcotics, the effectiveness of cooperation still needs to be improved through policy harmonization and the utilization of technology. The conclusion of this study emphasizes the importance of policy harmonization, enhanced inter-agency cooperation, and the optimization of technology to strengthen efforts to combat drug trafficking. Recommended measures include the establishment of an integrated database system, specialized training for law enforcement personnel, and the use of modern technology such as drones to expand surveillance coverage without being constrained by the vastness of the land border area between Indonesia and Malaysia in West Kalimantan. Keywords: Bilateral cooperation, drugs trafficking, Indonesia-Malaysia border, law enforcement.