The article examines the books of Vilnius University professor Michał Pełki-Poliński from the collection of the library of St. Volodymyr University, the collection "Library of the Volyn Lyceum", from the collection of literature in Polish of the department of library collections and historical collections of the Institute of Bibliography of the Vernadskyi National Library of Ukraine. The results of the research of Ukrainian, Polish, and Lithuanian researchers, which contain materials about the scientific activity of Michał Pełka-Poliński, are analyzed and his important role in the development of mathematical science in Lithuania and Poland is emphasized, the influence of his works on the teaching of mathematics in educational institutions of Galicia and Volyn. Information about the scientist's scientific work is provided, his scientific connections with Ukraine are noted. Bibliographical information about books authored by Polinsky from the funds of the Vasyl Stefanyk National Scientific Library of Ukraine in Lviv. His printed and handwritten works are indicated, his library work, his bibliophile preferences, and collecting achievements are highlighted. Bibliographical and historical information about books from his private library is provided and information about its history is presented. Bibliographical materials on the study and attribution of book marks on the books of Michał Pełka-Poliński are represented.