Leo Slezak (German pronunciation: [ˌleːo ˈslɛzak]; 18 August 1873 – 1 June 1946) was a Moravian dramatic tenor. He was associated in particular with Austrian opera as well as the title role in Verdi's Otello. He is the father of actors Walter Slezak and Margarete Slezak and grandfather of the actress Erika Slezak. ()