Born in Dresden, Germany, Berger spent some years as a child in India and South America. She lived there later on as well, working as a clerk and a piano teacher, before borrowing enough money for the trip back to Germany. At age 26, she secured a position as a soubrette soprano at the Semperoper in Dresden and had her first success as Hannele in Paul Graener's opera Hanneles Himmelfahrt, based on Gerhart Hauptmann's play The Assumption of Hannele. She later held leading positions at the Vienna State Opera, the Berlin State Opera, and the Deutsche Oper Berlin. Berger also gave concerts in Japan, the United States, and Australia.
Her discography features complete recordings of Die Zauberflöte (as the Queen of Night, conducted by Sir Thomas Beecham, 1937–38, for EMI), and Rigoletto, with Jan Peerce and Leonard Warren, conducted by Renato Cellini (1950) which was the first complete opera recording (with a few minor cuts) made in the United States by RCA Victor for commercial release. It is also the first complete opera ever released on long-playing (LP) records.
Berger appeared at the Metropolitan Opera during the 1949/50 and 1950/51 seasons, in Der Rosenkavalier (opposite Eleanor Steber and Risë Stevens, conducted by Fritz Reiner and directed by Herbert Graf), Rigoletto (with Warren, then Enzo Mascherini), Die Zauberflöte, and Il barbiere di Siviglia (with Giuseppe Valdengo). She also sang Woglinde and the Waldvogel in Der Ring des Nibelungen, with Kirsten Flagstad and Helen Traubel alternating as Brünnhilde.
At 60 years of age, she left the stage and taught as a professor in Hamburg and Essen, where she died in 1990. She was buried at the Zentralfriedhof, Vienna. In 1992, the Bästleinstraße in Dresden was renamed the Erna-Berger-Straße in her honour.
- Maria Ilona (1939)
- Falstaff in Vienna (1940)
- The Swedish Nightingale (1941)
- Whom the Gods Love (1942)
- Erna Berger: Die singende Botschafterin [The Singing Ambassadress], by Karla Höcker, Rembrandt Verlag, 1961.