Frey died from a combination of complications from rheumatoid arthritis, acute ulcerative colitis, and pneumonia
TMZ reported the cause of death was a combination of complications from rheumatoid arthritis, acute ulcerative colitis, and pneumonia.
The Michigan native was a founding member and guitarist of the 1970s band the Eagles, which produced one of the biggest rock hits of all time: Hotel California.
Frey had been battling intestinal issues for months and had surgery in November. TMZ added in the last few days his condition took a turn for the worse.
His illness forced the Eagles to pull out of their Kennedy Center Honors appearance in December.
At the time, the band said he needed major surgery that would require a lengthy recovery, added the site.
The star was a major part of the Eagles, helping them land in the Rock And Roll Hall Of Fame with several classics.
He co-wrote and sang most of the Eagles hits, including Take It Easy, Tequila Sunrise, Lyin' Eyes, New Kid In Town and Heartache Tonight. He wrote many of those hits with co-founder and frontman Don Henley who released a statement about his bandmate's passing that said: 'He was like a brother to me; we were family, and like most families, there was some dysfunction. But the bond we forged 45 years ago was never broken.
'We built something that has lasted longer than anyone could have dreamed. But Glenn was the one who started it all. It will be very strange going forward in a world without him in it. But I will be grateful, every day, that he was in my life. Rest in peace, my brother. You did what you set out to do, and then some.'
Other stars took to social media to send their condolences including legendary comedian Steve Martin who tweeted: 'Shocker. My friend from the early days, and important member of Eagles, has died. We loved you, Glenn Frye.'
When the Eagles split up in 1980, the musician went off on his own and found success.
His single The Heat Is On was a chart topper after it appeared in the 1984 film Beverly Hills Cop.
He also came out with You Belong to the City, which was used often in commercials.
Frey contributed the song Flip City to the Ghostbusters II soundtrack, and Part of Me, Part of You to the soundtrack for Thelma & Louise. During his solo career, Frey had 12 charting songs in the U.S. Top 100
Frey also appeared in several episodes of Miami Vice.
In 1994 he reunited with the Eagles. They launched their Hell Freezes Over tour which was a massive success. In 2012, he released he released his first solo album in 20 years, After Hours, featuring covers of pop standards from the 1940s to the 1960s.
As a member of Eagles, Frey won six Grammy Awards, and five American Music Awards. The Eagles have sold over 120 million albums worldwide and were inducted into the Rock and Roll Hall of Fame in 1998, the first year they were nominated.
He is survived by his wife Cindy with whom he has three children.