This research report examining the extent to which supervision contributes to improvement of academic performance in Tanzanian Primary schools. Specific objectives in this study were; examining the contribution of supervision on improvement of academic performance, to assess the current situation of school supervision in terms of responsibilities, to identify supervision challenges that hinder academic performance, and to determine measures that could be taken for improving supervision. The study entails five (5) chapters whereas; chapter one explains introduction, chapter two holds literature review, chapter three presents research methodology, chapter four presents data presentation, analysis and discussion, and chapter five is summary, conclusions and recommendations. The study was carried out in Nyamagana Municipal. The sample size involved was one hundred and fourteen (114) respondents, whereby key informants were; Municipal Education Officer, Chief Inspector and Inspectors. Other respondents were Head teachers, Academic teachers and teachers. The study used mixed methods approach in which triangulation method was employed. In this study sampling procedures were purposive and systematic sampling, and data collection instruments were interview, questionnaires and documentary review. Research findings based on specific objectives mentioned earlier, and data analysis was done with the aid of Statistic Package for Social Science (SPSS) and Microsoft Excel for quantitative, and in qualitative data was done by using descriptive form. The study found that; supervision is done very rare in schools, and it is done once per year, whilst other schools are not supervised at all in a year. There is huge contribution of supervision on improvement of academic performance such as; high pass rate in pupils’ academic performance, improved teaching professional, xv improved primary school leaving education and improved extracurricular activities. Moreover, the study found that, there are supervision challenges that hinder academic performance, some of them were; lack of fund, lack of knowledge and experience, lack of supervision facilities and lack of in service training. Finally, the study determined measures that could be taken for improving school supervision, some of them were; provide adequate funds, provide enough facilities and provide in service training. The study recommended the following; government is required to provide enough funds, prioritize education matters, Inspectorate department should plan their work properly, moreover; further studies are needed concerning other factors which contribute on improvement of academic performance, further studies needed in different places as well as finding out all issues related to supervision. Finally, the data were presented through pie charts and tables and figures in quantitative, whereas, in qualitative data were presented through description form.