The concept of “book culture”, which entered the domestic book-study discourse in the 1980s, is currently one of the central ones for both historical-book and theoretical-book studies. However, it has not yet received a conventional definition in Russian science. The purpose of the article is to formulate a definition of book culture based on the interpretative theory of culture and theoretical and methodological achievements of medialogy dominating in modern socio-humanitarian knowledge. The authors show the general theoretical context of the formation of the concept of “book culture”.