This study explored cybercrimes in Academic Libraries of Tertiary Institutions in Yobe State. Two (2) objectives set to guide this study were; to identify the types of cybercrimes perpetrated in academic libraries in Yobe State and reveal factors that influence cybercrime in academic libraries in Yobe State. Qualitative research methodology and multiple case study research design were employed. Data was collected using in-depth Semi-interview and document analysis. A sample of 6 participants was used for the study. Moreover, all the narratives from the 6 participants? were used for analysis. The data was analyzed using grounded theory Analysis. The findings revealed that the types of cybercrime perpetrated in Academic Libraries of Tertiary Institutions in Yobe State are cyber phishing, cyber bullying, impersonation, viewing of classified and pornographic materials. The factors that influences cybercrime includes poverty, technical know-how, lack of system security, lack of disciplinary action, lack or poor cyber policy, inappropriate monitoring and user’s negligence. Finally, the study recommended The Management of Federal University, Gashua, Federal Polytechnic, Damaturu and Federal College of Education (Technical), Potiskum to establish a quick response website where victims can report cybercrime cases along with digital forensic laboratory that would report cybercrimes related issues to the Management. And The Government and the Management of Federal University, Gashua, Federal Polytechnic, Damaturu and Federal College of Education (Technical), Potiskum should provide student Work-Study Programs to alleviate the financial pressures that drive students toward cyber fraud as a means of survival.