Angry musicians will protest outside this year's Grammy Awards ceremony over a decision to cut 31 ethnic and minority categories from the industry's top awards, Reuters reported.

Organisers of the protest hope dozens of musicians and fans of Latin jazz, gospel and blues music will join in the demonstration, before attending an alternative concert.

About 23,000 people have signed a petition demanding the Recording Academy reinstate Grammys for Native American and Hawaiian music, and reverse cuts in categories for Latin jazz, gospel, R&B and blues as part of a major overhaul last year.

Paul Simon, Carlos Santana, Bonnie Raitt and Bobby Sanabria are among the dozens of high-profile artists who have so far spoken out against the decision.

Spokesman Robert Sax says the protest will be held outside the Staples Centre in Los Angeles on Monday AEDT as stars like Rihanna, Chris Brown, Bruce Springsteen and the Beach Boys arrive to perform at music's biggest night.

The protesters will later celebrate at a Los Angeles nightclub, with performances by two-time Grammy winner Oscar Hernandez, John Santos and Bobby Matos.

"We are holding this concert to remind music fans about all the great music that has been eliminated from the Grammys," Matos said.

"To paraphrase what Frank Sinatra said at the first Grammy Awards in 1959, 'Remember, the awards are about excellence, not popularity'."

Rapper Kanye West leads this year's field of Grammy contenders with seven nominations, followed by Adele, Bruno Mars and Foo Fighters.