The purpose of the publication is to reveal and show the essence and content of the category "correctional rehabilitation of a criminal" in the philosophical and legal commitments of N. M. Yadrintsev. Guided by the hermeneutic methodology and textual analysis of the ideological political and legal heritage of the Siberian intellectual, we have emphasized that he associated the content of the definition of "correctional rehabilitation of a criminal" with moral.
 It is shown that in N. M. Yadrintsev's ideology appeal to the spiritual world of the man, to the moral principles of the life of an individual had a serious impact on the terminological apparatus used by the educator.
 It has been established that, supposedly, the leader of the regionalist movement can be considered one of the founders of penitentiary sociology, which arose at the overlap of sociological science and penitentiary law.
 The authors come to the conclusion that the definition of "correctional rehabilitation of a criminal" in the lexical and terminological apparatus of N. M. Yadrintsev, an ideologist of Siberian democratic regionalism, was used mainly in its content sense. The Siberian educator was primarily concerned with the nature of this category. In general, he understood the correctional rehabilitation of prisoners as a complex diverse process that has an immanent and permanent content.