Basing on a variety of historical and modern sources, the article seeks to reconstruct the biography of the famous composer and piano teacher Ivan Pratsсh (c. 1750–1818). His contacts in the musical circles of St. Petersburg of the late 18th and early 19th centuries, as well as little-known aspects of his activity as the author of keyboard and chamber music are covered in detail, including new data on three of his large-scale compositions: Fandango for keyboard, Grand sonata for cello and keyboard, and Transcription of Mozart’s piano quartet Es-dur K. 493 for two keyboards. As an appendix to the article, a detailed list of Pratsсh’s musical oeuvre is published for the first time, covering information on every work by the composer discovered to date. © 2022, Moscow State Tchaikovsky Conservatory. All rights reserved.