The article examines the philosophical discussions at the Faculty of Philosophy of Leningrad State University during the Khrushchev “thaw”, initiated by the need to study the phenomenon of science and resulted in the organization of the Leningrad philosophical school. Having analyzed the issues brought up by the Leningrad philosophers and the research methodology they used, the authors conclude that this school mainly developed problems of science philosophy. Therefore, the definition of the Leningrad school as an ontological one (as opposed to the Moscow gnoseological school), which is widespread in Russian historical and philosophical literature, is far from being correct. Moreover, it makes it difficult to see the relevance of the philosophical achievements of the Leningrad thinkers since it provokes to consider their ideas exclusively in the context of the disputes around the definition of matter, which took place among the theorists of dialectical materialism in Soviet times. On the contrary, considering the works written by the Leningrad philosophers in the 1950s–1960s from the point of view of the current philosophy of science allows us to better understand the philosophical innovations and original ideas of the Leningrad school. Particular attention is paid to the analysis of the views of V.I. Svidersky and V.A. Shtoff, the founders of the Leningrad school of philosophy of science. The authors also consider the works of A.D. Aleksandrov, rector of Leningrad State University (1952–1964), and those of the deans of the Faculty of Philosophy of Leningrad State University V.P. Tugarinov (1951–1960) and V.P. Rozhin (1960–1969), who contributed to the popularization of scientific-philosophical doctrines at the university and helped to organize candid discussions. The views of some other Leningrad philosophers of science, e.g. A.S. Mamzin, L.O. Reznikov, G.A. Podkorytov, V.P. Bransky, A.S. Carmin, are mentioned as well to trace back the development of the Leningrad school.