As in other developing countries, contraceptive use among adolescents is low and only one in twenty adolescents is reported to use contraceptives inKenya. Pregnancies early in life expose adolescents to health complications. Establishing perceptions that affect contraception and factors that influence those perceptions is important in developing appropriate programs and policies to increase contraceptive use prevalence among adolescents. We used primary data from a household survey using a systematic random sampling in eight administrative divisions inNairobiCountyin 2010. The study utilized information collected using structured interviews, focus group discussions (FGDs) and in-depth interviews (IDIs). The findings revealed that perceptions on parental approval, adolescent approval, ability to get contraceptives for self, knowledge of how to use contraceptives and sexual partner communication had significant effect on contraception. The narratives showed that parents, teachers and service providers had negative perceptions and discouraged contraception among adolescents thereby influencing use. Parents and teachers had inadequate knowledge and skills to communicate sexuality messages creating potential environment likely to have indirect negative influence on adolescents’ perceptions on contraception.