Moore was born in Austin, Texas, moving to California in 1936. He was an integral part of the Nat King Cole Trio for a decade, from 1937 to 1947, appearing on most of Cole's records during that period. A superb and influential guitarist, Moore was himself influenced by Charlie Christian. Barney Kessel once said that Moore practically created the role of the jazz guitarist in small combos. He also recorded with Lionel Hampton, Art Tatum (1941), the Capitol Jazzmen, and Lester Young. Moore was voted top guitarist of 1945, 1946, and 1947 in the Down Beat readers' poll.
Moore's post-Cole career was not very successful. He played with his brother Johnny Moore in the Three Blazers from 1947 to the mid-1950s, after which the group declined in popularity following the departure of pianist/singer Charles Brown. Moore also recorded three records for the Verve and Tampa labels during 1953 and 1954. After that he was outside of music with the exception of one Cole tribute album in 1965. Eventually he left music altogether and settled in Los Angeles, where he worked as a bricklayer.
As member of Nat King Cole Trio
- The Complete Capitol Recordings Of The Nat King Cole Trio (Mosaic #MD18-138, 1991) 18-CD box set
- Nat King Cole And The King Cole Trio (1938-1940) (Savoy Jazz #ZDS-1205, 1989) [recorded for the Davis & Schwegler Transcription Service]
- The Complete Early Transcriptions Of The King Cole Trio: 1938-1941 (Vintage Jazz Classics #VJC-1026, 1991) 4CD [recorded for the Standard Transcription Library]
- The King Cole Trio: The MacGregor Years, 1941-1945 (Music & Arts #911, 1995) 4CD [recorded for the C.P. MacGregor Transcription Service]
- King Cole Trio: Transcriptions (1946-1950) (Blue Note-EMI #60184, 2005) 3CD [recorded for the Capitol Transcriptions Service]
As member of Johnny Moore's Three Blazers
- Charles Brown - The Chronological Charles Brown 1947-1948 (Classics #1147, 2001) - note: includes tracks that Oscar recorded with pianist/vocalist Charles Brown when they were both members of Johnny Moore's Three Blazers.
- Johnny Moore's Three Blazers Featuring Oscar Moore - Los Angeles Blues: Complete RCA Recordings 1949-1950 (Westside #WESD-217, 1998) 2CD
- Floyd Dixon - His Complete Aladdin Recordings (Capitol-EMI #36293, 1996) 2CD - note: includes all 21 tracks that Oscar recorded with pianist/vocalist Floyd Dixon when they were both members of Johnny Moore's Three Blazers.
- 1954: Oscar Moore Trio (AKA Galivantin' Guitar) (Skylark Records SKLP-19 [10" LP]; Tampa Records TP-22 [12" LP] reissue) - with Carl Perkins
- 1955: Oscar Moore Quartet (AKA The Fabulous Oscar Moore Guitar) (Tampa Records TP-10 [12" LP]; Charlie Parker Records PLP-830 [12" LP] reissue)
- both of these albums have been reissued on one CD by V.S.O.P. Records  in 1995.
- 1955: Swing Guitars (Norgran Records MGN-1033 [12" LP]; Verve Records MGV-8124 [12" LP] reissue) - note: Oscar's group shares this album with Tal Farlow's group, and Barney Kessel's group [4 tracks by each artist].
- 1957: Presenting Oscar Moore (Omega Records/Omegatape ST-7012 [issued on reel-to-reel tape only])
- 1957: Have You Met Inez Jones (Riverside Records RLP-12 819 [12" LP]) - note: Oscar's group used as backing musicians for vocalist Inez Jones.
- both of these albums have been reissued on one CD by Fresh Sound Records  in 2012.
- 1965: We'll Remember You, Nat (Surrey Records SS-1013 [12" LP]) - with Gerald Wiggins, Joe Comfort
With Lionel Hampton
- The Chronological Lionel Hampton & His Orchestra 1939-1940 (Classics #562, 1996) CD - note: includes the first session that Oscar (and Nat King Cole) recorded with Hampton for RCA Victor in 1940: House Of Morgan, I'd Be Lost Without You, Central Avenue Breakdown, Jack The Bellboy.
- The Chronological Lionel Hampton & His Orchestra 1940-1941 (Classics #624, 1996) CD - note: includes the second session that Oscar (and Nat King Cole) recorded with Hampton for RCA Victor in 1940: Dough-Ra-Me, Jivin' With Jarvis, Blue (Because Of You), I Don't Stand A Ghost Of A Chance With You.
With Art Tatum
- The Chronological Art Tatum 1940-1944 (Classics #800, 1996) CD - note: includes the 4 tracks that Oscar recorded with Tatum & His Band (featuring vocals by Big Joe Turner) for Decca in 1941: Lucille, Rock Me Mama, Corrine Corrina, Lonesome Graveyard Blues.
With The Capitol International Jazzmen
- The Chronological Nat King Cole 1944-1945 (Classics #861, 1996) CD - note: includes the 4 tracks that Oscar (and Nat King Cole) recorded with an all-star group (Bill Coleman, Buster Bailey, Benny Carter, Coleman Hawkins, John Kirby, Max Roach, and vocalist Kay Starr) for Capitol in 1945: You Can Depend On Me, If I Could Be With You (One Hour Tonight), Stormy Weather, Riffamarole.
With Anita O'Day
- The Complete Recordings 1949-1950 (Baldwin Street Music #BJH-302, 1998) CD - includes the 5 tracks that Oscar (and Nat King Cole) recorded with O'Day for the C.P. MacGregor Transcription Service in 1945: Ain't Misbehavin', Penthouse Serenade (When We're Alone), Lonesome Road, I Can't Give You Anything But Love, Rosetta.
With Lester Young
- The Lester Young–Buddy Rich Trio With Nat King Cole (American Jazz Classics #AJC-144546, 2014) CD - note: includes the two live tracks Oscar recorded with this group at the AFRS Jubilee (#184) in Hollywood on March 20, 1946: These Foolish Things (Remind Me Of You), Lester Leaps In.
With Benny Carter
- A Jumpin' Jubilee: The Jam Sessions 1945-1946 (Storyville #2054, 2002) CD - note: includes the 3 live tracks Oscar recorded with this group (Benny Carter, Willie Smith, Charlie Parker, Nat King Cole, Buddy Rich) at the AFRS Jubilee (#186) in Hollywood during April 1946: Tea For Two, Body And Soul, Cherokee.
With Ray Charles
- The Complete Swing Time And Down Beat Recordings 1949-1952 (Night Train International #2001, 1997) 2CD - note: includes the 4 tracks that Oscar recorded with Charles for Swing Time in 1950: I Wonder Who's Kissing Her Now, All To Myself, Lonely Boy, Baby Let Me Hold Your Hand.
With Illinois Jacquet
- The Chronological Illinois Jacquet 1951-1952 (Classics #1376, 2004) CD - note: includes 3 of the 4 tracks that Oscar recorded with Jacquet for Clef/Verve in 1951: Lazy Blues, Pastel, All Of Me. The fourth song, Speedliner is found on The Chronological Illinois Jacquet 1947-1951 (Classics #1254, 2002).
With Sonny Criss
- note: Oscar recorded 4 tracks with Criss when they were both members of Billy Hadnott's Orchestra (actually a sextet) for Federal in 1952: Ooh Chica b/w My Ideal (Federal 12084), and Junk Wagon b/w Limehouse Blues (Federal 12096).