This study was designed to investigate the security measures in Imo State Public Library Owerri. the research objectives were to identify security problems in Imo State Public Library, Owerri, the determine the extent to which security problems affects the library operation as well as identifying security measures adopted in Imo State Library Board, Owerri. The population for the study is 95, the research is survey, the analysis were done with percentage and tables, frequency count were used for data analysis. Findings showed that mutilation and theft are the major security problem identified in Imo State Library Board Owerri, it was also revealed that the extent to which security problems affect library operations in very high. The findings equally identified major security measures adopted by the library under study in combating security problems among other things.