The main objective of this paper is to evaluate the impact of deregulation of downstream petroleum sector on Nigeria's economy between 2007 and 2015. It is a qualitative study built on secondary data which were textually analysed. Upon the pivot of public choice theory as a framework for interrogating the themes of the paper, the study posits that the effective deregulation of downstream petroleum sector offers the necessary recipe and vitality for stemming economic rent-seeking attitudes by the elites and political class, and ultimately lead to economic buoyancy. Other recommendations of the paper are capable of addressing the policy gaps/failures identified.