The purpose of the article is to consider the concept of "musical thesaurus" as a specific repository of musical knowledge and a means of understanding musical culture in modern conditions of information enrichment of humanitarian discourse. The methodology is based on concepts and theoretical conclusions in the field of the humanities. Research methods: analytical are used to study the structure of a musical thesaurus, as well as the principles of a musical thesaurus-dictionary building; historical - considering the musical thesaurus as a repository of musical knowledge, which is a product of the corresponding historical periods; cultural, comparative - in understanding the relationship between the musical thesaurus and other ways of preserving knowledge, as well as in the process of converting the attributes of a particular historical culture into an individual thesaurus of creativity; semantic - in revealing the specifics of the refraction of the cultural thesaurus in the composer's personal thesaurus, which, in turn, is reflected in the musical work. The scientific novelty of the study lies in the fact that the structure, forms, and properties of the musical thesaurus are analyzed, and the features of the preservation of musical knowledge in the thesaurus of this art form are revealed for the first time. Conclusions. The musical thesaurus is a repository of musical knowledge, a kind of information space that includes potential and relevant cultural meanings embodied through intonation systems, and a specific context in material and ideal forms. It should be noted that even such a general view of the musical thesaurus does not exclude the need to clarify its affiliation. Since this concept includes two components, it is necessary to classify the thesaurus according to two parameters: the musical proper and the generic one. The first parameter, in turn, points to two different signs, one of which divides the thesaurus into amateur and professional, and the second into their different types. An amateur thesaurus is divided into an ordinary and educated listener, a neophyte and an informed, highly and poorly educated, from the point of view of general knowledge, as well as thesauri representing various sociocultural, age, national and other groups. Among the professional thesauruses, there are composer, performing (also polysyllabic), musicology (which includes all areas of musical science). It is advisable to identify related professions that are associated with music and form their musical (professional) thesauruses. These include the field of music publishing, music libraries, libraries, music museums, where most often they combine museum work with scientific practice, musicology, and the like. The generic parameter for the classification of musical thesauruses provides for their division into collective and individual, sociocultural, and personal. The same mechanics of mutual influence operates here as in any other thesaurus in a modus of ideal form. [ABSTRACT FROM AUTHOR]