Adele Passy-Cornet (22 January 1838 – 2 November 1915) was a German opera soprano singer.
Born in Braunschweig, Passy-Cornet was a daughter of the opera singer couple Julius and Franziska Cornet. After she received her first artistic lessons by her mother, Passy-Cornet went to Hamburg and took singing lessons there. Afterwards she sang in Austria and appeared among other things at concerts at the Viennese court.
She later performed as a coloratura also in her homeland, among other places in Braunschweig, Hamburg and Hannover. At the age of 27, Passy-Cornet got an engagement at the Theater am Kärntnertor in Vienna in 1865 and made her debut there with outstanding success as the "Queen of the Night". Although she achieved great success in a short time and could choose her engagements, she soon devoted herself only to singing occasional concerts. She married, and her daughter was the singer Anna Prasch-Passy.
Passy-Cornet founded a private singing school in Vienna and directed it until 1881, before being appointed singing teacher at the Franz Liszt Academy of Music in Budapest. In 1892 she gave up this office and returned to Germany. She settled in Nuremberg and taught singing there.