The article examines the architectural features of buildings and spaces in the largest Roman Catholic educational institutions on the terrains of modern Ukraine; highlights and analyzes the principles underlying the architecture formation of theological educational institution of the Roman Catholic Church; determines the conception of architectural and space-planning organization of separate sacred, academic, administrative, and household buildings, recreational, entertainment, and sports spaces on the campus territory of theological educational institutions of the Roman Catholic Church; outlines the practical recommendations for project designers. Roman Catholic educational institutions in Ukraine are represented by the range of buildings and complexes in Western, Central, and Southern Ukraine. The most accomplished from the view point of its architectural and space-planning decisions is the complex of Major Theological Seminary of Lviv Archdiocese and Theological Institute in Briukhovychi village near Lviv. Taking into account the architecture of the mentioned complex and the complex of Lviv Theological Seminary of the Ukrainian Greek Catholic Church, the article distinguishes the major principles and foregrounds the set of practical recommendations concerning project design of theological educational institution of the Roman Catholic Church in Ukraine. In particular, the architecture development of theological educational institution of the Roman Catholic Church is based on the following principles: confessionalism and ecumenism; multi-education; sacredness; secularism; inclusiveness; flexibility and mobility; traditionalism and modernism. Also, as per the outlined architectural and space-planning conception, theological multi-educational center as an architectural complex is the combination of theological and educational departments of all levels of theological education in Ukraine and forms the uniform architectural ensemble, the main ideological and visual object of which is a temple. The specified principles and conception will be useful for future project designers during the process of determining architectural and space-planning organization of such an ideologically and functionally difficult object as theological educational institution (or center) of the Roman Catholic Church in Ukraine, which will foster creation of new qualitative projects and construction of modern institutions of theological education of the Roman Catholic Church.