This study aims to analyze legal certainty in the implementation of the death penalty in Indonesia from the perspective of Islamic criminal law. It examines the concept of legal certainty, the mechanisms for implementing the death penalty, and factors supporting and hindering its realization within the national legal system. This study employs normative legal research using statutory, conceptual, and comparative approaches. Data were obtained through a literature review of legislation, the Qur’an, Hadith, fiqh, Islamic criminal law literature, and relevant scholarly journals. The findings indicate that legal certainty in the implementation of the death penalty has not been fully realized due to prolonged waiting periods, complex clemency and judicial review mechanisms, procedural inconsistencies, and limited coordination among law enforcement agencies. Islamic criminal law provides a comprehensive framework through the principles of la jarimata wa la ‘uqubata illa bi nash (no crime or punishment without a legal textual basis) and dar’ al-hudud bi al-syubhat (avoiding hudud punishment in cases of doubt), supported by strict evidentiary standards, protection of defendants’ rights, and al-‘afwu (forgiveness) in qisas cases. Supporting factors include a clear legal basis, sentencing parameters, evidentiary standards, division of authority, and protection of victims and convicted persons. Inhibiting factors include uncertainty over execution timing, divergent interpretations, limited public awareness, and weak inter-agency coordination. The study concludes that criminal law reform should strengthen procedural certainty while integrating justice, humanity, and public interest as core values of Islamic criminal law.