This study examined the impact of commandants' supervisory role performance on the management of prison schools in Nigeria. It's aimed at examining the impact of commandants' supervisory role performance on communication; to determine the impact of commandants' supervisory role performance on the maintenance of school facilities in prison schools; commandants' supervisory role performance on delegation of duties to staff in prison schools among others. To achieve the objectives of the study, descriptive survey research method was used and all the eight hypotheses were subjected to Pearson product moment correlation statistical analysis. The respondents for the studies are the commandants and directing staff/instructors of the schools under study. The population of study was 626. A sample of 120 was used for the study through stratified random sampling and simple descriptive survey techniques. Questionnaire was the only instrument for the study; content validity method was employed for the verification of the questionnaire. The data for the study was collected through visit to the sampled prison schools in Nigeria and was subjected to descriptive and inferential statistics of the PPMCC at 0.05 level of significance; simple percentages, item means and standard deviation, and the results were presented in a tabular form. The study revealed that commandants' strict supervision on staff enhanced effective lines of communication in prison schools; that commandants' strict supervision of staff helped to improve the level of school facilities maintenance and utilization in prison schools; that commandants' strict supervision of staff made delegation of responsibilities to staff very effective in prison schools among others. The researcher however among others recommended: that commandants should ensure that adequate and effective lines of communication be maintained at all times; discipline should be maintained by both staff and trainees diligently; that the maintenance of school facilities should be the priorities of both staff and trainees; that school should not exist in isolation of the community but should ensure harmonious co-existence for the development of the school among others and suggestions were also proffered for further studies