Managing human capital, directing enterprises or institutions, as well as broadly understood management has always been a task requiring special skills. It is mainly about the knowledge of issues in the area of operation of a given entity, but also of widely developed "soft skills". Essential for the development of these competencies is - experience in executive positions, which the legislator very often requires from people applying for management positions in state units. The essential element of the work is to present the tasks of the members of the supervisory board, whose nature is the same or similar to the tasks of management staff. That is to prove the thesis set out in the title of the article that the function of a supervisory board member is a managerial function. The study contains an analysis of the principal legal acts from the systemic and institutional perspective in Poland. This article is a theoretical work, based mainly on cognitive research, using the historical-legal, dogmatic-legal and comparative methods.