The article aims to contextualize the architectural features that should be present in a leper colony in the early twentieth century and show the complete requirement compliance on the conception and construction of Leprosarium São Roque, in Piraquara (PR). To this end, it highlights the national health legislation on the subject and the architectural response to these hygienist impositions. Then, it goes back to Paraná and the trajectory of leprosy coping, form de mid-1890s until 1926, with the inauguration of São Roque. Finally, based on government messages, journal articles, architectural drawings and photographs, it analyses the characteristics of its architectural complex and emphasizes the full compliance with the requirements and the spatial solutions for the treatment of leprosy patients.