A corelational research design was employed to examine if a relationship exists between professional development (PD) and teachers job performance in preparatory schools setting, and to investigate whether the various elements of PD have independent effects on teachers’ job performance. A total of 5 preparatory schools, 80 teachers and 10 educational leaders were involved in the study. Mean, standard deviation, Pearson r correlation coefficient and multiple regression analysis were applied for the data analysis. The results indicate that PD has a significant and positive relationship with teachers’ job performance in the preparatory schools, but nonetheless, a weak one. Group development is the most positive predictor of teachers’ job performance in the preparatory schools. However action research and curriculum development showed very low prediction on the teachers’ job performance. Lack of employer support, lack of incentives and certification, poor quality and irrelevant PD practices were reported as major implementation challenges of professional development. It is recommended that standards of teachers job performance evaluation that includes instructional planning and delivery, assessment of learning, learning environment, professional ethics, interpersonal relations and management skills should be introduced to school system so as to make the PD practices relevant to the schools job performance. The involvement of teachers in PD activities should be planned; and need-based and up-to-date programs (e.g. new learning technologies, innovative pedagogies) with the involvement of teachers need to be identified and initiated. These calls for necessary support and resources allocation form the relevant stakeholders.