This study was conducted to investigate the use of forensic evidence in criminal investigation among investigators of the Nigerian Police Force. Using a mix-method research design, the study was guided by four research questions and two null hypotheses. The study used criminal investigators and staff of forensic units as the population for the study, of which 225 were initially drawn as the sample for the study. However, from the returned instrument for data collection, 189 respondents were used for the final sample. Data was collected using a semi-structured questionnaire and key informant interview from senior serving and retired police officers. Using an interview schedule and statistical analysis technique, the data were critically analyzed. Results from the study showed that while police investigators reported usage of various forms of forensic evidence, significant challenges such as poor training, inadequate funding, political interference, and slow judicial process all contribute to limit the effective use of forensic investigation in the conduct of criminal investigations. On the basis of this result, it was recommended that specialize units be established for forensic investigations which should be adequately funded.