The government of Kenya recognizes the importance of implementing strategic plans in public schools as the key approach of management of institutions, strategic planning is very crucial in realization of management outlook for the Kenyan vision 2030, relatively little research has investigated the ways public schools implement strategic plans. This study was designed to assess the effect of monitoring and evaluation on implementation of strategic plans in public secondary schools in Kenya. The study was guided by a mixed method Research design. The target population for the study was 9 sub-county education officials, 284 chairpersons of Board of management, 284 principals and 284 senior teachers in Bungoma County. The study sample comprised of 9 sub-county education officials, 85 chairpersons of Board of management, 85 principals and 85 senior teachers. The respondents were selected using purposive and simple random sampling technique and the instruments for data collection were questionnaires, interview schedule and document analysis. Data was analyzed using mean, standard deviation, frequency, Pearson Correlation Coefficient and Multiple Regression to establish relationships and variable traits while themes were derived from narrative data. The findings of this study revealed that monitoring and evaluation dimension has a significant relationship with implementation of strategic plans in public secondary schools. It is recommend that it is very crucial that the public secondary schools conduct monitoring and evaluation on the strategic plans, this will help the educational institutions to gather valuable information that will provide valuable insights in the strategic plans implementation across the education sector