The article examines the Polish indefinite pronouns against the background of their Russian equivalents. The author systematizes the Polish linguists’ views on the Polish indefinite pronoun system, discusses different approaches to studying these units: from the XIX-century methodologies to the modern ones. The paper analyses in detail the basic criteria to classify indefinite pronouns - according to the method of formation. Special attention is paid to the correlation of the semantic components of indefinite pronouns belonging to different groups. Such ambiguity causes problems for linguo-didactics and the Polish-Russian translation studies and requires further investigation.