Michael’s publicist, Cindi Berger, said he died at his home in Goring, England. She did not reveal the cause of death but said he had not been ill.
"It is with great sadness that we can confirm our beloved son, brother and friend George passed away peacefully at home over the Christmas period," his publicist said in a statement.
British producer Nile Rodgers was stunned. “I was just at his house the morning of the 23rd. So crazy,” Rodgers tweeted.
Michael rose to fame as a teenybopper idol in the 1980s music duo Wham! He had hits like “Wake Me Up Before You Go-Go," and “Freedom.”
Throughout his career he sold over 100 million records worldwide, won numerous Grammy awards and recorded with the likes of Aretha Franklin, Ray Charles, Luciano Pavarotti and Elton John.
His debut solo album, “Faith,” sold more than 20 million copies and showed a vocal range lauded by critics.
That album produced one of Michael’s first major controversies, as critics slammed the hit 1987 tune “I Want Your Sex” as encouraging promiscuity in the midst of the AIDS epidemic.
Michael responded by writing "Explore Monogamy" on the leg and back of a model in the song’s music video.
He was made for MTV. Many of Michael’s videos featured him in tight jeans and leather jackets, surrounded by beautiful women.
That image appeared in jeopardy when Michael was arrested for lewd conduct in a public toilet in Los Angeles in 1998 by an undercover cop.
But instead, Michael released a single, “Outside,” that made light of the incident. He also began speaking openly about his sexual orientation.
Michael continued releasing successful albums and drawing big crowds. His last album, "Symphonica," was released in 2014.
His run-ins with the law continued, as well, many stemming from his use of drugs while behind the wheel.
Michael was an admitted user of marijuana and prescription sedatives.
He was also arrested a second time in public toilets — this time in North London in 2008 for drug use, an incident that prompted him to apologize to his fans and promise to get his life in order.
He also offered an apology to "everybody else, just for boring them."