Dissertation (MA Public Administration)Teacher motivation has become an important issue given their responsibility to impart knowledge and skills to learners. Consequently, this study investigated the effects of motivation on the performance of secondary school teachers in Nyamagana District, Mwanza Region. Specifically, the study sought to find out whether motivation of teachers had any effect on their morale to perform. A descriptive survey research design was adapted where a total sample of 100 respondents including secondary school teachers, headmasters/headmistresses and Nyamagana District Education Officers were consulted. The primary data was collected using structured questionnaires and consequently, both qualitative and quantitative data were collected. Research findings revealed that the performance of teachers was bad due to the fact that their motivation was inadequate. Besides, the majority of the teachers performed their activities with low morale as evidenced from absence of teaching allowance, low salary, promotion delays, absence of teachers‟ houses, and bad treatment of their headmasters/headmistresses, government negligence to teachers‟ demands and among others. A significant positive relationship between motivation and performance was also found to exist. On the other hand, a positive relationship was also revealed between extrinsic motivation and performance of teachers, implying that extrinsic motivation affected the performance of secondary school teachers in Nyamagana district. In order to improve teacher motivation and performance at work, the researcher recommended increase in the salary of teachers to match the increased cost of living, provision of accommodation to teachers, promote teachers in time as well as instituting awards for good performance, among others.