The draft of the letter by former President of the Academy of Sciences of the USSR S. I. Vavilov addressed to J. V. Stalin and supposedly dated 1948 points to Vavilov attempting to streamline the introduction of scientific censorship in the sphere of significant research in physics. In Vavilov’s opinion, the prohibition had a negative impact on other branches of science as well, including humanities. This letter was a second one that Vavilov sent to Stalin. As his appeal to entrust control over information security procedures to the institutions of Academy of Sciences of the USSR had no effect, Vavilov made reference to the experience of his foreign colleagues, who were free to discuss their latest scientific achievements, and proposed to organize a special censure body, within which, he hoped, most authoritative scholars would be able to keep the scientific discussion alive. Both Vavilov’s letters to Stalin seem to be directly connected with the consequences of implementation of the resolution of the Council of Ministers of the USSR of June 8, 1947 no. 2009 ‘On formation of the list of information classified as state secret, disclosure of which is punishable by law.’ This document replaced the resolution of April 27, 1926 ‘On the approval of the list of information, the contents of which is classified as specially protected state secret.’ Obviously, attempts of Vavilov, who sought to continue the policy of compromise and cooperation with the Soviet power started by S. F. Oldenburg - the Permanent secretary of the Academy of Sciences of the USSR until 1929 - and to retain the freedom of scientific discussion at least in some degree, primarily, in the spheres most relevant for the national defense industry development (such as nuclear physics) and thus to contribute to their further development, were unsuccessful. The resolutions accepted by the Politbureau of the Central Committee of the VCP(B) and the Council of Ministers of the USSR (both earlier and later) strengthened state control over all spheres of scientific activity. Publication of several journals in foreign languages was forbidden, regime of severe secrecy was introduced in the museum sphere.