Abstract: The possibility of submitting to arbitration controversies arising out of concession contracts for oil and natural gas exploitation is foreseen by Brazilian Federal Law 9.478/1997. However, according to the Brazilian Arbitration Act and the Brazilian Civil Code of 2002, the arbitrability of such contracts is limited by the nature of the rights in dispute. One of the arguments against arbitration, in these cases where the Public Administration is one of the contracting parties, is the principle according to which public interests may not be alienate. On the other hand, this orientation does not deprive Public Administration of exercising activities of private nature. For such purpose, one shall discriminate both acts that can be practiced by Public Administration, jus imperi and jus gestionis. The "theory of finalities" also provides in the same sense, differentiating primary public interest from the secondary one. In other words, in one hand, the concession contracts for exploitation and production of oil and natural gas are subject to the limits imposed for the Public Administration, in what concerns the supremacy of the public interest, while, in the other hand, they deal with economic activity exploitation and thus are of private nature. Hence, the issue of the arbitrability is attached to a factual analysis of each case, as disputes concerning rights which may or may be alienate might eventually occur.