Penelitian ini mengkaji penerapan hukum pidana internasional terhadap kejahatan massal yang dilakukan rezim Khmer Merah di Kamboja pada periode 1975-1979 di bawah kepemimpinan Pol Pot. Kejahatan yang mengakibatkan kematian sekitar 1,7 juta jiwa ini mencakup pembunuhan massal, penyiksaan, kerja paksa, dan genosida terhadap kelompok etnis tertentu. Menggunakan metode yuridis normatif, penelitian ini menganalisis bentuk kejahatan internasional berdasarkan Statuta Roma 1998, Konvensi Genosida 1948, dan Konvensi Jenewa 1949, serta mengkaji konsep pertanggungjawaban pidana individu dalam hukum pidana internasional. Hasil penelitian menunjukkan bahwa tindakan rezim Pol Pot memenuhi unsur kejahatan terhadap kemanusiaan, genosida terhadap etnis Cham dan komunitas Vietnam, serta kejahatan perang. Berdasarkan prinsip pertanggungjawaban individu dan tanggung jawab komando dalam Pasal 25 dan 28 Statuta Roma, Pol Pot dapat dipertanggungjawabkan secara penuh atas kejahatan internasional yang terjadi selama kekuasaannya, terlepas dari posisinya sebagai kepala negara. Penelitian ini menegaskan bahwa tidak ada impunitas bagi pelaku kejahatan internasional, termasuk pejabat negara tertinggi sekalipun. Kata kunci: Hukum Pidana Internasional, Pertanggungjawaban Individu, Khmer Merah. Abstract This research examines the application of international criminal law to mass crimes committed by the Khmer Rouge regime in Cambodia during 1975-1979 under Pol Pot's leadership. These crimes resulted in approximately 1.7 million deaths and included mass killings, torture, forced labor, and genocide against specific ethnic groups. Employing a normative juridical method, this study analyzes the forms of international crimes based on the Rome Statute 1998, Genocide Convention 1948, and Geneva Conventions 1949, while examining the concept of individual criminal responsibility in international criminal law. The findings demonstrate that the Pol Pot regime's actions fulfilled the elements of crimes against humanity, genocide against the Cham ethnic group and Vietnamese community, and war crimes. Based on the principles of individual responsibility and command responsibility under Articles 25 and 28 of the Rome Statute, Pol Pot can be held fully accountable for international crimes committed during his rule, regardless of his position as head of state. This research affirms that there is no impunity for perpetrators of international crimes, including even the highest state officials. Keywords: International Criminal Law, Individual Responsibility, Khmer Rouge.