This study was designed to assess the effect of theft and mutilation on the use of information resources in Francis Sulemanu Idachaba Library University of Agriculture Makurdi, Nigeria. The study has four specific objectives with its corresponding research questions. The study used descriptive research design; the population of the study was 150 library staff. All the 150 library staff was used for the study as they were relatively small as such there were no need for sampling. A self-designed questionnaire was used as instrument for data collection. The collected data was analyzer using descriptive statistical analysis. The findings of the study revealed the forms of theft and mutilation, effects of theft and mutilation and ways of preventing theft and mutilation of information resources in libraries.