Born in Zagreb, Croatia as Zinka Kunc (pronounced [zîːŋka kûnt͡s]), she studied with the Wagnerian soprano Milka Ternina and her assistant Marija Kostrenčić.

Her debut in her native Croatia, at the National Theatre in Zagreb, took place five weeks later as Marguerite in Charles Gounod's Faust.

After an early debut in Dresden (November 5, 1928, also as Leonora), her teacher, Ternina, was not pleased and much work commenced to perfect her technique.

The 2004 Opera News article "Zinka Takes Off"[2] stated that the name change was deemed necessary since the gentlemen at the Met feared the "implications inherent in what they predicted would be the standard American mispronunciation — but they were never forthright with her about it".

[citation needed] In 1940, Milanov was one of the featured soloists in a radio performance of Beethoven's Missa Solemnis, along with Jussi Björling (tenor), Alexander Kipnis (bass), Bruna Castagna (mezzo), and the Westminster Choir.

Among her pupils were Betty Allen, Grace Bumbry, Christa Ludwig, Regina Resnik, Dubravka Zubovic and Milka Stojanovic.