Eusebius Mandyczewski (Ukrainian: Євсевій Мандичевський Ėvsevij Mandyčevśkyj, Romanian: Eusebie Mandicevschi; 18 August 1857, Molodiya – 13 August 1929, Vienna) was a Romanian musicologist, composer, conductor, and teacher. He was an author of numerous musical works and is highly regarded within Austrian, Romanian and Ukrainian music circles.