Gruber receives a $7,500 cash award and engagements at Alice Tully Hall and around the United States, including the premiere of a new work by George Tsontakis.
She has previously appeared with New York City Opera, Los Angles Opera, and Opera Theatre of St. Louis, among other companies.
The $5,000 second prize went to baritone Thomas Meglioranza; third prize, worth $3,500, went to baritone Tyler Duncan. Soprano Amanda Forsythe received an honorable mention and a prize of $1,000.
The Naumburg Competition rotates each year between piano, violin, and voice. Previous winners of the vocal award include Dawn Upshaw and Shirley Verrett.