This study investigated the "Impact of Staff Development Programmes on the Performance of Teachers in Secondary Schools in Yola Metropolis, Adamawa State". The study raised five objectives, these are: to determine the impact of in-service training on the performance of teachers in secondary schools, examine the impact of conference on the performance of teachers, assess the impact of workshop on the performance of teachers, assess the impact of workshop on the performance of teachers, ascertain the impact of seminar on the performance of teachers and find out the impact of mentoring on the performance of teachers in secondary schools in Yola metropolis, Adamawa state. Research questions and hypotheses were also formulated in line with the raised objectives of the study. Many related literature were reviewed based on the raised objectives. Descriptive survey design was employed for the study. The population of the study was 1,458 teachers. Random sampling technique was used to derive sample from each zonal office. Thus, the sample of the study was 285 teachers and 10 ministry of education officials. Data was collected personally in 13 schools through the use of constructed questionnaire. The collected data was presented by use of frequency and percentages, and later analysed using Analysis of Variance (ANOVA) statistical technique. Five hypotheses were tested, thus hypotheses 1,3, 4 and 5 were retained. While, hypothesis 2 was rejected and Scheffe test was employed to ascertain the extent of differences of opinions of the three categories of respondents. The finding of the study revealed that teachers' performance was positively impacted through regular in-service training, workshops, seminars and mentoring. On the basis of findings and conclusions, the study recommended that, there should be formal policy guidelines for training of teachers, opportunity should be made for every teacher to attend in-service training programme, educational conferences etc. an adequate funds should be provided by the ministry of Education for staff development programmes. A unit in the ministry of Education should be created for training purposes