The Oswaldo Cruz Institute's Mollusk Collection (CMIOC) in Brazil has served as a vital repository for these species, diligently curated since 1948, focusing on freshwater ecosystems and the transmission of parasitic diseases. This study presents a comprehensive dataset derived from the CMIOC's Planorbidae collection. The dataset encompasses crucial information, including taxonomy, collection details, geolocation data, and catalog reference data, providing an in-depth understanding of the biodiversity and distribution of these medically significant snails. Specimens were meticulously identified using morphological characteristics, with data validation and quality control conducted via the integrated publishing toolkit of the Fundação Oswaldo Cruz (FIOCRUZ) and the Global Biodiversity Information Facility (GBIF) data validator tool. The dataset reveals the extensive geographic distribution of Planorbidae species, with records spanning 55 countries across six continents. In Brazil, the dataset covers 26 states and the Federal District, providing occurrence records in 592 municipalities. Notably, Biomphalaria species emerge as the most well-represented genus in the CMIOC, with Biomphalaria glabrata, B. straminea, and B. tenagophila playing significant roles in the transmission of schistosomiasis in the country. The dataset further elucidates the distinct geographic distributions of these species within Brazil, highlighting areas of coexistence and specific ecological preferences. This dataset serves as a crucial resource for further research in the fields of evolution, ecology, and epidemiology, particularly concerning medically relevant species and their role in public health. Its availability in the Sistema de Informação sobre a Biodiversidade Brasileira (SiBBr) and integration with the Global Biodiversity Information Facility (GBIF) enhances its accessibility and potential for fostering advancements in scientific knowledge and disease management. The CMIOC continues to be a vital repository for the preservation and study of Planorbidae biodiversity, contributing significantly to the broader understanding of freshwater ecosystems and the transmission of parasitic diseases.