This article discusses the types of formal legal sources that, until 1986, constituted the system of nuclear law in communist Poland. The time frame of this study was determined, on the one hand, by the state's commencement of legislative activity in the area in question (1952) and, on the other hand, by the adoption and entry into force of the first Polish Atomic Law (1986). It was the first legal act of this rank in Poland that comprehensively regulated the safety of nuclear energy and ionising radiation. Furthermore, the new act largely streamlined the previously opaque system of norms, which consisted of acts of varying rank and form originating from numerous state authorities.