A performing police service is crucial for any country in ensuring the enforcement of laws, maintaining public order, and preventing crime. Mental health among police officers is very important for their performance. However, mental health issue remains a major challenge within the police service in Kenya. The failure to prioritize mental health has led to increased suicide risk, increased stress and burnout, higher risk of mental health disorders, and reduced resilience and coping skills among police officers in Kenya. Therefore, the study sought to assess the effect of trauma management on the performance of police in Kamukunji Sub-County, Nairobi County. The study was anchored on the institutional theory of Stress. A descriptive survey research design was adopted. The target population consisted of 104 respondents: 12 Administration police, 5 critical infrastructure police units, 8 Kenya police dog units, 4 general service units, 26 general duty police, 18 traffic police departments, and 30 criminal investigation department police from Kamukunji Sub County. A census design was employed to include all responders since the study population was manageable. The study sample included all 110 intended respondents. Primary data was gathered through structured questionnaires and interviews. A pilot study was conducted in Embakasi West Subcounty to test the equipment. Pre-tested questionnaires examined face validity to improve reliability. Cronbach's Alpha was used for internal consistency. The study used both descriptive and inferential statistics. The analyzed data were presented using tables. The study concluded that there is a positive and statistically significant correlation between trauma management and the performance of police in Kamukunji Sub-County, which implies that better trauma management enhances the performance of police in Kamukunji Sub-County. The study recommended that authorities overseeing police departments should allocate sufficient resources to enhance existing mental support services, such as counseling and peer support programs, ensuring accessibility and effectiveness for all officers.