A Dissertation Submitted in Partial Requirements for the Masters Degree of Public Administration (MPA) of Mzumbe University.Training and performance are very important factors in terms of school success and achievements. If changes occur in external environment then it is necessary for a school to adopt that change because it may influence to gain competitive advantages. For this case, schools require skilled and competent teachers’ employees. Training plays an important role in improving the performance of teachers in school because it increases the productivity of teachers’ and the goals can be achieved in an efficient way. Changes in the provision of secondary education is one of the key point the government of Tanzania that has been doing since the time after independence that is after 1960’s to which at least all the essential for the provision of education were provided by the government. This study based on the assessment of the role of training and development programs in improving the performance of public and private secondary school teachers in Ilala district, Tanzania. The nature of the study based on social science thus, the study was qualitative and it used descriptive survey design, whereby primary and secondary data were collected by the use of observation, questionnaires and interviews to arrive at the conclusion. The corrected data was analyzed through SPSS and EXCEL software. The findings of the study revealed that there is a significant and positive relationship between teacher’s training and their performance. There have been studies on the role of training on performance; however there is a lack of research on the role of training in improving the performance of both public and private school teachers in Tanzania. The study seems to feel the gap. The study also concluded by highlighting different aspects of training to be included in providing the training program to public and private secondary school teachers. The study would help different secondary schools to improve the performance level of teachers that would lead to better and effective performance of secondary school teachers.