Pyotr Ilyich Tchaikovsky, the great Russian composer, conductor and teacher, kept diaries for most of his life. He recorded in them everything that happened to him and his surroundings, recorded intimate thoughts and observations, judgments about contemporaries, his own and others' secrets. I didn't show them to anyone and eventually burned almost all the records. The remaining papers (11 notebooks) were collected by his brother Modest, and subsequently published in 1923 by his other brother, Hippolyte, together with Nikolai Timofeevich Zhegin, the first director of the Tchaikovsky House Museum. The notes in the "Diaries" belong to the hand of Nikolai Zhegin.In this edition, the "Diaries" of Pyotr Ilyich Tchaikovsky are published together with the full text of the memoirs of him, his close friend and colleague, professor of the Moscow Conservatory. "Memoirs of P. I. Tchaikovsky" by Nikolai Kashkin, written with great warmth and love shortly after the composer's death, is the first creative biography of Pyotr Tchaikovsky and contains extremely valuable evidence of Tchaikovsky's artistic taste and personality traits.