Journey guitarist Neal Schon wants his bandmate to stop playing the rock band’s songs at political events. 

A lawyer for Mr. Schon sent a cease-and-desist letter to the band’s keyboardist, Jonathan Cain, after he performed “Don’t Stop Believin’” at an event last month at Mar-a-Lago that former President Donald Trump attended. The letter cites a Twitter video of Mr. Cain on stage playing and singing the song. 

“Although Mr. Cain is free to express his personal beliefs and associations, when he does that on behalf of Journey or for the band, such conduct is extremely deleterious to the Journey brand as it polarizes the band’s fans and outreach,” said the letter, which is dated Dec. 16. “Journey is not, and should not be, political.” 

Mr. Schon also wrote on Twitter that Journey’s music shouldn’t be connected with politics. “To me our music is sacred and for all,” he said.

“Neal Schon should look in the mirror when he accuses me of causing harm to the Journey brand,” Mr. Cain said Thursday in a statement.

Other musicians have taken issue with their songs being used at political events. The Rolling Stones in 2016 asked Mr. Trump not to play the band’s songs at rallies while he was running for president. Tom Petty sent former President George W. Bush a cease-and-desist letter over the use of his tune “I Won’t Back Down” during Mr. Bush’s 2000 campaign.

The letter from Mr. Schon’s lawyer said Journey’s perceived affiliation with Mr. Trump has fans “up in arms,” and included a list of tweets from people saying they no longer support the band. 

“This has caused, and continues to cause, irreparable harm to the Journey brand, its fan base and earning potential, especially in light of the forthcoming tour,” the letter said.

Messrs. Schon and Cain are taking Journey on a 50th-anniversary tour next year. “Don’t Stop Believin’” was written by Mr. Schon, Mr. Cain and former lead singer Steve Perry.

Released in 1981, it had a revival decades later when it was played in the final episode of the HBO hit “The Sopranos” and the first episode of TV show “Glee.”

Write to Joseph Pisani at joseph.pisani@wsj.com