Lowering fertility levels and improving maternal and child health in sub-Saharan Africa has been a policy objective for decades. Most efforts have focused on women, with little or no involvement of men. The type of marriage, however, has rarely been considered as a possible factor that could influence contraceptive use, and therefore could have an effect on fertility and reproductive health. This study thus assesses contraceptive use by sexually active men among three marriage types—singles, polygamous, and monogamous. The study was based on data on sexually active men age 15-49 sampled in the 2013 Nigeria Demographic and Health Survey (NDHS). The study showed that, overall, 30% of the sampled population were currently using contraception, with condom use as the dominant method (66%). The level of contraceptive use was significantly higher among sexually active single men, at 68%, compared with 19% among monogamous married men and 9% among polygamous men. Other factors influencing contraceptive use among sexually active men included wealth status, educational attainment, ethnicity, region, religion, and age. The study concluded that in view of the wide variation in contraceptive use by marriage type in Nigeria, efforts to increase contraceptive prevalence should give more consideration to policies and programs that promote consistent use of contraceptives particularly among married men.