The Polish National Assembly is a constitutional governing body, endowed with unique powers that cannot be exercised by any other body. However, the status of the Assembly as a separate state organ raises doubts. Since the restoration of the Assembly, its position in the system has changed significantly, which was related to the multiple modification of the competences of this organ. The evolution of this organ in 1989-2020 allows treating it as an interesting research case. Especially since the competences of the National Assembly are crucial for ensuring the continuity of state power.