Abstract In the wake of seemingly normalized criminality and its unabated wave in Nigeria and the need for concerted efforts to understand its pervasiveness, this paper examined the issues and challenges in the Nigeria Criminal Justice System (CJS). The administration of criminal justice in Nigeria has evolved significantly over time, mirroring the complexities and challenges of its diverse and dynamic society. It plays a pivotal role in maintaining law and order, protecting citizens' rights, and ensuring justice. However, it faces numerous issues and challenges that impede its effectiveness. This paper examined these challenges, focusing on systemic inefficiencies, procedural delays, corruption, lack of adequate infrastructure, and the inadequate training of law enforcement officers. One of the most significant concerns is the overwhelming backlog of cases, exacerbated by limited judicial personnel and poorly equipped courts, resulting in prolonged pretrial detention and prison congestion. Additionally, corruption within the police force and judiciary further undermines public confidence in the system, as financial and political influences often distort the course of justice. Governed primarily by the Administration of Criminal Justice Act (ACJA) 2015, along with similar state-level laws, the system is designed to promote fair and efficient justice. The ACJA introduced reforms aimed at reducing delays in criminal proceedings, safeguarding the rights of suspects and victims, and improving the overall efficiency of the judicial process. However, despite these improvements, the Nigerian criminal justice system still grapples with significant issues such as systemic corruption, inadequate infrastructure, and resource shortages that hinder its effectiveness. This paper has made recommendations that requires an overhaul of the Nigerian criminal justice system requiring comprehensive reforms, including the modernization of legal frameworks, better training for judicial officers, investment in infrastructure, and the strengthening of anti-corruption mechanisms to restore public trust. Addressing these challenges is essential for ensuring that justice is served fairly and efficiently in Nigeria.