A review article focusing on two catalogues published by the National Library in Warsaw in the series Polonica from the 16-18th Centuries in the Roman Libraries, Catalogue of Early Printed Books in the Library of Pontifical Institute of Ecclesiastic Studies in Rome and Catalogue of Polonica in the Biblioteca Casanatense. The main attention was paid to the scope of the material described in them (significant differences in the selection) and registration of provenience (Polonica provenience) as an element indicating the popularity of Polish subject matter and works in foreign collections, dislocations of the collections, or activity of the Poles in exile. Both catalogs are discussed against the background of the other four publications from the series, showing differences in the selection of materials and elements of descriptions (provenance), and briefly the history ofregistration of Roman Polonica.