Teacher's professional development is a driver of excellence in schools to add value to school improvement. Therefore, the aim of this research was to investigate the role of teachers’ personal characteristics, perception towards Continuous Professional Development (CPD) and support of school leaders in the implementation of teachers’ continuous professional development in the case of Finote Selam town secondary school, Ethiopia. To achieve this, Ecological Theory as a theoretical lens and a convergent parallel mixed design were utilized. Data was gathered through a questionnaire from a sample of 304 teachers that were selected using a comprehensive sampling method and 11 interviewees. As results, except teachers’ perception towards CPD program, which is moderate, teachers’ views about the composite scores of school leaders’ contribution of CPD, and teachers’ implementation of CPD are at the low level. Teachers’ implementation of CPD has no correlation with age, length of service, and perception of teachers towards CPD. However, there is a significant, strong, and positive relationship between teachers’ implementation of CPD and school leaders’ contribution to CPD. The support of school leaders explains 39.6 % of the total variance of teachers' CPD implementation. Finally, lack of good school culture among use in professional development activities, lack of commitment, lack of funding, and lack of common understanding related to CPD were the most prominent challenges affecting teachers’ implementation of CPD. The findings provide theoretical implications to the literature and practical implication to educational institution leaders by identifying the main challenges of teachers in the implementation of CPD.
