This paper explores critical success factors in the implementation of community based projects in kiambu county, Kenya. Most of the community based projects experience major hurdles in their life cycle and barely overcome the implementation stage. This study specific investigated how Community participation, management of funds, institutional capacity and monitoring and evaluation influence successful implementation of community based projects. The researcher a descriptive survey design followed by stratified random sampling technique to segment the project strata's of the targeted a population of 141 community based projects. He further used purposive and simple random sampling techniques to zero in to the key respondents of 86 CBP leaders.This paper concludes that community participation, management of funds, institutional capacity and monitoring and evaluation of the projects positively influence the implementation of community based projects in Kiambu County.The recommends that there is a need to actively involve the community members in the actual planning of the project, practicing financial record keeping and proper budgeting, allocate capacity building resources to the members and project managers and finally enhance monitoring and evaluation while implementing a Community based project.