The purpose of the study was to examine the impact of teachers' motivation on job performance in Government secondary schools in Tanzania. Specifically, the study examined the effect of teachers' fringe benefits on their job performance; investigated the impact of teacher's remedial classes payments on Job performance; determined the effect of teacher's remuneration on job performance and examined the effect of teachers’ promotion after their studies to their job performance. The Maslow’s Theory of needs guided this study. The study was carried out in four government secondary schools selected from Kahangara Division, Magu District. Descriptive research design was used to collect data from the selected population in which both quantitative and qualitative data collection approaches were employed. A total of 115 respondents comprising head of schools, teachers and school board members participated in the study. Questionnaires were used to collect data from teachers and interviews guide were used to collect data from Head of Schools (HOS) and School Board Members (SBM). SPSS version 20 package was used to analyze quantitative data in which statistics such as frequency, percentage and figures were presented while content analysis was used to analyze qualitative data. The study found that few schools do provide fringe benefits as a way of motivating teachers. With respect to the findings, teachers’ promotion especially in public secondary schools was to a large extent still a problem of major concern. However, there was an influence of teachers' remuneration on the job performance. Therefore, motivation was needed as a wheel hub for effective and efficient job performance. The study recommends that school community members, school boards, society and government should provide motivation to teachers to make them stay in their work station and deliver the service to their best level.