The study examined the relationship between performance evaluation and organization performance. A case study research design using mixed methods approach was used to answer the study questions. A sample size of 126 respondents was considered for the study, 105 respondents participated, giving a response rate of 83%. Simple random sampling and purposive techniques were used to select the participants. Data analysis involved frequencies, means and inferential statistics such as correlations and the coefficient of determination. The main finding of the study was that performance management system at KCCA do not link promotion to performance achievement and it was also found out that that performance management system at KCCA do not facilitate implementation of strategy by motivating desired level of performance. It was therefore concluded that performance evaluation positively influenced the performance of KCCA. The study therefore, recommends the need for top leadership of KCCA to tag promotion to performance. This will motivate employees and subsequently increase performance.