Abstract: Abstract: The subject of research in this paper is a range of cross-disciplinary problems related to the concept of "cultural system". Examination is conducted on the existing culturological approaches towards the definition of cultural systems; the question is raised on the appropriateness of using this concept in analyzing the spheres of human activity that are not traditionally associated with the concept of “culture”. The author dwells on the mathematics, medicine and religion, proving the effectiveness of culturological research of these spheres of life as the cultural systems. The theoretical and methodological framework is based on the concept of systematicity of culture. This article employs the analytical, comparative, and semiotic methods. The following conclusions are made: 1) any cultural system, besides its specific components, includes the general cultural components that typical to all cultural systems that are part of the single complex of “culture” and are not specific to its separate cultural systems; 2) the number of cultural systems determined within the culture largely depends on the research perspective, and is virtually limitless. The author’s special contribution, which also determines the scientific novelty of this article, lies in the proposed model of interaction of various cultural systems within a single culture.