Despite the success in initiating adolescents living with HIV on antiretroviral therapy (ART), questions remain about factors affecting viral suppression. In Kenya, only 63% of adolescents (aged 10– 19 years) on ART had achieved viral suppression in 2016. We investigated factors associated with viral suppression among adolescents initiated on ART before November 30, 2017 in Homa Bay County, Kenya.