Aim: The aim of the article is to analyse the selected aspects of the social and scientific activities of Prof. Marian Walczak (1923–2020). Particular attention is paid to the activity of Prof. Marian Walczak for the Polish Educational JOANNA 118 MADALIŃSKA-MICHALAK Research Association, PERA, of which he was the Secretary General in the years 1981–2020. Methods: A historical analysis of source materials. Results: Bringing closer the history and development of the Polish Educational Research Association, PERA, the chosen examples of tasks carried out by Professor Walczak in cooperation with the authorities of the Society, which are part of the broad spectrum of scientific, organizational and programmatic activities of PERA have been presented. The article shows that Prof. Marian Walczak’s social and scientific activities have resulted in very important achievements. Conclusions: Prof. Marian Walczak has gone down in the memory of posterity with his activities for the history of the Polish Teachers’ Union, the history of education in Poland in the twentieth century and the history of the Polish Educational Research Association. The presented analyses show that the scientific output of Prof. Marian Walczak and his involvement in the social scientific movement are very significant for the development of the Polish pedagogical thought, educational practice and the social scientific movement.