Brett Steele, his manager, said the country music hall of fame singer died at his home in Wartrace, Tenn., early Wednesday.
Louvin was diagnosed with cancer last year and underwent surgery, but continued to schedule performances and even put out an album. He was one of several stars invited to a welcome home performance of the Grand Ole Opry last year after floods damaged the Opry house.
According to the Country Music Hall of Fame, the unique sound of Charlie and his brother, Ira, was highly influential in the history of the genre. The hall inducted them in 2001.
Among their hits were "I Don't Believe You've Met My Baby," which was No. 1 in 1965; "When I Stop Dreaming"; "Hoping That You're Hoping"; and "You're Running Wild."
The brothers decided to disband their duo in 1963. Two years later, Ira died in a Missouri car accident. Charlie later recalled that differences in personality and Ira's drinking created friction between them, but said they probably would have reunited if Ira had lived.
Charlie Louvin recorded regularly after his brother died. His album "The Longest Train" was released in 1996. His biggest solo hits were "See the Big Man Cry" in 1965 and "I Don't Love You Anymore" in 1964.
They influenced harmony acts from the Everly Brothers onward. Emmylou Harris had a hit with their "If I Could Only Win Your Love" in 1975. The Notting Hillbillies recorded the Louvins' "Weapon of Prayer" in 1990.
Interest in his music resurged as Louvin reached his 80s. In 2007, his first studio album in years, "Charlie Louvin," boasting appearances from artists like George Jones and Elvis Costello, was nominated for a Grammy as best traditional folk album.
A year later, his "Steps To Heaven" was nominated as best Southern, country or bluegrass gospel album. It was one of two albums he put out in 2008; the other was "Charlie Louvin Sings Murder Ballads and Disaster Songs."
Louvin said in a 1979 Associated Press interview that he and his brother, reunited, would have become country music superstars.
"If we were together today, we could be the hottest group. That's where the music is - the Louvin Brothers sound. Everybody is trying the Louvin sound."
He recalled in a 2007 AP interview that Ira "was extremely hard to get along with when he drank, and he drank too often." But he said his brother was phenomenally talented as a songwriter, taking ideas proposed by Charlie and turning them into finished songs.
"My job was to listen to people ... and if they said something that caught your ear that would make a good title ... I would write it down and I'd give it to Ira."
A complete song, Louvin recalled, would "come to him like, God, like he was reading it off of another piece of paper. ... He was nice enough to put my name on the songs also."
The duo had become members of the Grand Ole Opry in 1955, and Charlie Louvin remained an Opry performer for more than 50 years.
During one stretch of touring in 1955, Elvis Presley was the brothers' opening act. That second billing didn't last long, he recalled in 2007.
"It didn't take a month until they dropped the name 'Presley' and nearly the backdrop of the entire stage was ELVIS. He got big quick, very quick, but he was a good kid."
He laughed when he said he was "kinda like the people in the audience - I didn't know what he's doing. ... My brother said he's the only man he'd ever seen that could wear his clothes on out from the inside with all his shaking."
Charlie Louvin was born Charles Loudermilk in Henager, Ala., in 1927. He and Ira, born in 1924, worked in the fields on the family farm and began singing together as teenagers, developing the harmony that would become their trademark.
"I can remember my brother and I singing together when I was five and he was eight years old," Louvin told The Associated Press. "He already knew how, and he was teaching me."
They worked on radio stations in Knoxville, Tenn., and Memphis, Tenn., in the 1940s, and signed their first record deal with Apollo in 1947.
Charlie Louvin said in 1992, "I hear the Louvin Brothers are more famous in Japan than they were in the United States."
