This study was carried out to determine the impact of affirmative action policy on the quality service delivery in the public service sector of Kenya. The study was carried out on the premise that there is a relationship between affirmative Action implementation and the quality of service delivery in the public service sector of Kenya. A lot of resources are spent on affirmative action programs. Not much is known about the impact of Affirmative action on quality of service delivery in the Public Service Sector. Primary and Secondary data were obtained from the ministries of Gender, Social Development and Children, Higher Education, Science and Technology and Ministry of state in the office of the president using a questionnaire. The study adopted a comparative case survey design and involved a combination of both qualitative and quantitative data. Qualitative analysis was done by calculating percentage counts and frequency counts and tests of hypotheses carried out. The study revealed that implementation of an affirmative action policy in the public service sector impacts positively on the quality of service delivery and again that the quality of service delivery as indicated by cost effectiveness, accountability, employee participation, productivity and transparency was higher in the Ministry of Higher Education, Science and technology than in the Ministry of State in the Office of the President. Chi-square data analysis revealed that there is a significant relationship between affirmative action implementation in employment, promotion, training and career progression and the quality of service delivery in the public service sector of Kenya. The study recommends that in the future researchers should investigate the impact of affirmative action with respect to racial and ethnic differences and disability.