Daniel Ferro (10 April 1921 – 18 November 2015) was an American bass-baritone and voice teacher. He was known primarily as a teacher whose students have included many prominent opera singers, but he also had a career as a singer himself both on the concert stage and in opera and musical theatre.
Ferro was born in New York as Daniel Eisen to a Jewish-American family. His father was Joseph Eisen, born in the province of Galicia, in the Austro-Hungarian Empire, and his mother was Pauline Greenberg Eisen, born in Holyoke, Massachusetts to a father from New York and a mother from the Russian Empire, now southern Ukraine. He graduated from the Juilliard School of Music (in 1948) and from Columbia University. A Fulbright scholarship enabled him to pursue further vocal studies in Austria at the Salzburg Mozarteum and in Italy at the Accademia Chigiana and the Accademia Santa Cecilia. Early in his career he changed his surname from Eisen, the German word for iron, to Ferro, the Italian word for iron.
During the early 1950s, Ferro was member of the Graz Opera Company in Austria where his appearances included Mathis der Maler (Truchsess von Waldburg) and Parsifal (Titurel). He also appeared on European concert stages and toured with the Israel Philharmonic Orchestra. When Ferro returned to the United States in 1956, he took up an appointment as Associate Professor in the voice department at Butler University in Indiana. The 1960s found him in back in New York City, teaching at Hunter College and later at the Manhattan School of Music where he became chairman of the voice department. During that time, he also performed in both musical theatre and opera, including leading roles in musicals with St. John Terrell's Company and other , a revival of The Saint of Bleecker Street in New York City, and concert performances of Werther in Carnegie Hall and William Tell at Lincoln Center.