The new constitution promulgated in 2010 clearly state every Kenyan without discrimination is entitled to the highest attainable quality of health care, which is not reflected with the current challenge's men-who-have-sex with- men (MSM) continue to face in the sexual health service utilization. Kenya struggles in its response to this ongoing crisis amongst MSM in many areas including disease prevention, treatment, and HIV related stigma, prejudice, and discrimination. Currently little information is reported on MSM health services utilization. The wider spread of Sexual Transmitted Infections including HIV beyond the MSM community is real hence need for urgent intervention. Therefore, the overall aim of this study was to assess HIV services utilization among MSM in Nairobi County. This book will help in enhancing the HIV programs understanding of existing gaps and offer solutions, advocating and promoting safe sexual behaviours among MSM, reduce stigma and discrimination of MSM to enhance their willingness to use HIV services.