Mollie O'Brien (born October 25, 1952) is an Americana, bluegrass, R&B, and folk singer from Wheeling, West Virginia. She has released a number of Americana albums with her brother, Grammy-winner Tim O'Brien. She has also released five positively received solo albums. She is currently based in Denver, and regularly tours and performs with her husband, guitarist Rich Moore, as a duo. Together they have released one studio album, Saints and Sinners and a live CD, 900 Baseline. She has regularly appeared on shows such as A Prairie Home Companion, Mountain Stage, and contributed vocals to the Grammy-winning album True Life Blues: The Songs of Bill Monroe. She is known for her interpretations of classic songs by artists such as Tom Waits, Memphis Minnie, Willie Dixon, Chuck Berry, Si Kahn, Terence Trent D'Arby, and Kate MacLeod.