This paper examines the relationship of international law to sports law and the particular nature of so called Lex Sportiva2. The paper also researches whether Lex Sportiva (sometimes also called Lex Olympica) may be a subcategory of international law, or on the other hand whether it creates a different and independent type of rules of law in the sphere of the international practice of sports, with its sources being private international sports institutions. It has been said that the theory of international law maintains that “The law is a mandatory class. It establishes socially organised penalties and it is clearly distinguished both from the religious classes and the moral ones...”3 On the basis of this theory the paper examines whether the international sports institutions, notably the International Sports Federations and the International Olympic Committee are according to international law, international entities, i.e. bodies whose rules can be considered as international sports law.