Renowned soprano Montserrat Caballe, who brought opera into the pop charts by singing "Barcelona" with Freddie Mercury, died aged 85 early on Saturday, hospital officials said.
She was hospitalised from mid-September because of a vascular problem.
Born to a working-class Catalan family, Montserrat Caballe, who was named after a local monastery, received a first-class musical education.
Caballe released the song "Barcelona" with the Queen frontman Mercury in 1987 and it was used again during the 1992 Barcelona Olympics, a year after Mercury's death.
Her debut went down in opera history as one of the greatest overnight successes and she went on to tour the world in a career that spanned half a century.
After Mercury's death in 1991, the track was featured at the 1992 Summer Olympics and peaked at number 2 in the United Kingdom, the Netherlands and New Zealand.
In her performances, her versatility astounded fellow opera stars, with tenor Jose Carreras telling Catalunya Radio: "She could do everything from the purest bel canto all the way to Wagner's Tristan und Isolde".
Her voice was noted for its purity, precise control and power using superb technique and vocal shadings, as well as pianissimos, which were inspired by Spanish operatic tenor Miguel Fleta.
She went on to tour the world in a career spanning 50 years, garnering worldwide acclaim for her creamy voice and dramatic power.
In 2015, she was convicted of tax fraud and given a suspended sentence of six months in prison.
She went on to perform with the Metropolitan Opera, San Francisco Opera and Vienna State Opera, appearing opposite the likes of Luciano Pavarotti and Placido Domingo.