Medicine is one of the most important directions for the country development and has a fundamental position in the socio-economic policy of the state, ensuring the human health and well-being. With the development of medical technologies, the standards of medical care are also growing, and the requirements to healthcare facilities are becoming more stringent. In the conditions of dense urban development, the construction of a multi-purpose medical center that fully meets the standards may be problematic, and therefore the possibility of reconstruction of existing healthcare facilities to meet up-to-date requirements is being considered. The purpose of this article is to determine the possibility of reconstruction of multi-purpose healthcare facilities through densification of development; to analyze the methods of densification in relation to the territories of multi-purpose healthcare facilities; and to detect the architectural principles in the densification of development of multi-purpose healthcare facilities. The article authors also show the architectural techniques used in reconstruction with an increase in the technical and economic indices of the facility. The methodology of this research represents the analysis of academic papers, as well as the analysis and generalization of practical experience in the architectural design and reconstruction of multi-purpose healthcare facilities, including the personal experience of the article authors. The result of the research is the determination of the basic principles of the reconstruction of multi-purpose healthcare facilities, which make it possible to create the up-to-date typology of a healthcare facility, and have an impact on the formation of the architecture of multi-purpose healthcare facilities. The research is aimed at forming the up-to-date typology and architecture of multi-purpose healthcare facilities during reconstruction.