In a globe where scientific advancement, secular education and social mobility have defined age-old theories of how we look at the concept of marriage, the clamour for the legality of same sex marriage has been on the increase. Nations of the world are at disparity on the subject. In Africa, for instance, homosexuality has been frowned upon and is regarded as an act 'alien' and highly despicable. The paradigm is however different in the Western world where the cry for same sex marriage is at its peak. The Nigeria legislature has however, taken a decisive step to ensure that homosexual activities are nipped in the bud and are not extended widely into the society. This step has been taken through the successful passing of the Same Sex Marriage (Prohibition) Act 2013. This thesis takes a thorough study of the constitutionality of the Same Sex Marriage (prohibition) Act 2013.