In 1852, his friend Anton Rubinstein invited Theodor Leschetizky to take a teacher's position at the court of the Grand Duchess Yelena Pavlovna in St. Petersburg, Russia. He became one of the founders of the St. Petersburg Conservatoire of Music in 1862 and remained there as a head of the piano department until 1877.
After returning to Vienna, Leschetizky established one of the most prominent private piano schools in the world. Some of his notable students included Ignacy Jan Paderewski, Artur Schnabel, Fannie Bloomfield-Zeisler, Mieczyslaw Horszowski, Alexander Brailowsky, Benno Moiseiwitsch, Elly Ney, Ossip Gabrilowitsch, and Mark Hambourg.
Name variations: Teodor Leszetycki, Theodor Leschetizky, Theodor Hermann Leschetizky, Теодор Лешетицкий, Фёдор Осипович Лешетицкий, Федор Лешетицкий, テオドル・レシェティツキ