This paper is a study on the issues in cybercrime, offences and penalties, and challenges that provoke cyber policy established in Nigeria. It seeks to define what cybersecurity and cybercrimes are from the perspective of the National cybercrime law. The focus of this study, however, is to highlight crimes or offences considered to have an impact on national security, the related issues, the effects of cybercrimes, challenges, and prospects. The study concludes that the leading causes propelling Nigerians to indulge in cybercrimes are disorientation and the rate of unemployment