This work has developed the study of the economic analysis of law with a view to verifying the plausibility of applying its premises to Brazilian law, and in particular to Family Law, reformulated since the promulgation of the 1988 Republican Constitution, bearing in mind that most of its institutes are not economically appreciable. On the other hand, the primary aim of this theory, in the sense of its greatest exponent, Richard Posner, is that the law should always seek to maximise social wealth and, in conjectures in which the insertion of market guidelines is not feasible, it is imperative to formulate a market environment in order to achieve greater efficiency.