His death was announced by his biographer, Don Cusi.
Rising from a poverty-stricken childhood in Henderson, Tennessee, Arnold connected with the Pee Wee King Band as a singer and went on to a career in which he was named to the Country Music Hall of Fame and received the County Music Association's first entertainer of the year award.
Before his retirement from active singing, he released a new RCA album, "After All These Years," in 2005.
Arnold starred on the Grand Ole Opry in 1943, signed with RCA the following year but did not have a hit until 1946 with "That's How Much I Love You."
Coming under the management of Col. Tom Parker, Elvis Presley's manager, Arnold quickly scored a string of hits and graduated from radio to television.
Many in the country music industry disapproved of his merging country and pop, but with his smooth baritone he quickly gained the reputation of being country's version of Bing Crosby.
He sold more than 85 million records and had 147 songs hit the charts.
Among others, his hit singles include "Cattle Call," "Just Call Me Lonesome," "After Loving You," "I Want to Go With You" and "Tennessee Stud."
Arnold's wife, Sally, died earlier this year.
Reuters/Nielsen