Born in Tacoma, Washington, in December 1953, Schuur was blind from birth. She grew up in nearby Auburn, Washington, where her father was a police captain. Nicknamed Deedles at a young age, Schuur discovered the world of jazz via her father, a piano player, and her mother, who kept a formidable collection of Duke Ellington and Dinah Washington records in the house.
She was still a toddler when she learned to sing the Dinah Washington signature song, “What a Difference a Day Makes.” Armed with the rare gift of perfect pitch, Schuur taught herself piano by ear and developed a rich, resonant vocal style early on, as evidenced in a recording of her first public performance at a Holiday Inn in Tacoma when she was ten years old. She received formal piano training at the Washington State School for the Blind, which she attended until age 11. By her early teens, she had amassed her own collection of Washington’s records and looked to the legendary vocalist as her primary inspiration.
Schuur made her first record in 1971, a country single entitled “Dear Mommy and Daddy,” produced by Jimmy Wakely. After high school, she focused on jazz and gigged around the northwest. In 1975, an informal audition with trumpeter Doc Severinson (then the leader of the Tonight Show band) led to a gig with Tonight Show drummer Ed Shaughnessy’s group at the Monterey Jazz Festival. She sang a gospel suite with Shaughnessy’s band in front of a festival audience that included jazz tenor saxophonist Stan Getz, who in turn invited her to participate in a talent showcase at the White House. A subsequent return performance at the White House led to a record deal with GRP, which released Schuur’s debut album, Deedles, in 1984.
Schuur's debut album, Deedles, was released in 1984, the first of several recordings to showcase her vocal abilities. In 1985, while on tour in the Far East, Schuur met B.B. King when the two of them played a music festival in Tokyo. Schurr and King eventually made an album together, Heart to Heart released May 1994, which top the Billboard charts to number one. Twelve of Schuur's albums have reached the Top 10 Jazz Albums on Billboard history charts, including Diane Schuur: Live In London (2006)  She received her first Grammy for the album Timeless (1986), and the following year received another, for Diane Schuur & the Count Basie Orchestra (1987).
Schuur proved her staying power through the 1990s and into the 2000s, first with her 1991 follow up to Talkin' 'Bout You, Pure Schuur, and then with nearly an album a year from then on, including In Tribute (1992]), Love Songs (1993), Heart to Heart (1994), Love Walked In (1995), Blues for Schuur (1997), Music Is My Life (1999), Friends for Schuur (2000), and Swingin' for Schuur (2001). Late in 2003, Schuur released Midnight, featuring original songs written for the album by Barry Manilow. Manilow also performs alongside Schuur on the album, along with Alan Broadbent on piano, Chuck Berghofer on bass, and the drummers Harvey Mason and Peter Erskine.
Her second live album, Diane Schuur: Live In London, was released in June 2006. It is her first release on the GR2 Classics label, the 20th album of her career and was recorded at Ronnie Scott's in Soho, London.
In 2008 she released a new studio collection entitled Some Other Time.