Delaney may have been born Mattie Doyle south of Tchula, Mississippi,[2] but the researchers Bob Eagle and Eric LeBlanc suggest she was Mattie B. Delaney, born near Goodman, Mississippi.[4] Around 1927 she may have moved to Memphis, Tennessee. Contemporary witnesses remember seeing her perform at Swan Lake, Mississippi.[2] She recorded two songs for Vocalion Records in February 1930.[5] Her song "Down the Big Road Blues" was a variant of Tommy Johnson's "Big Road Blues".[6] One music journalist noted "Delaney issuing a matter-of-fact report in 'Tallahatchie River Blues'".[7] She was unusual for a female performer of the time, in that she played guitar accompaniment and sang topical songs. Nothing is known of her life after the recordings.[8]
Two of Delaney's songs were included on the compilation albumMississippi Girls (1928–1931), issued in September 1991.[9]