Purpose-The purpose of the paper is to demonstrate the role of property law in the period of systemic transformation of the state and economy, which is the period of the transition from command-and-distribution economy to market economy. Research method-Analysis of the sources of law, views of representatives of science of law and views of judicature. Results-It can be considered that this was a unique process in the history of the Polish political system and in the history of the Polish economy. Property law became the basis for the functioning of legal institutions specific to the market economy, such as for example, commercial companies.