Kirk was born Ronald Theodore Kirk in Columbus, Ohio, but felt compelled by a dream to transpose two letters in his first name to make Roland. In 1970, Kirk added Rahsaan to his name.
Preferring to lead his own groups, Kirk rarely performed as a sideman, though he did record with arranger Quincy Jones, Roy Haynes and had especially notable stints with Charles Mingus. He played the lead flute and solo on Jones' Soul Bossa Nova, a song popularized in the Austin Powers films (Jones 1964; McLeod et al. 1997).
His playing was generally rooted in soul jazz or hard bop, but Kirk's knowledge of jazz history allowed him to draw on many elements of the music's history, from ragtime to swing and free jazz. Kirk also regularly explored classical and pop music.
Kirk played and collected a number of musical instruments, mainly various saxophones, clarinets and flutes. His main instruments were a tenor saxophone and two obscure saxophones: the manzello (similar to a soprano sax) and the stritch (a straight alto sax lacking the instrument's characteristic upturned bell). Kirk modified these instruments himself to accommodate his simultaneous playing technique. He typically appeared on stage with all three horns hanging around his neck, as well as a variety of other instruments, including flutes and whistles, and often kept a gong within reach. Kirk also played harmonica, english horn, recorders and was a competent trumpeter. He often had unique approaches, using a saxophone mouthpiece on a trumpet or playing nose flute. He additionally used many extramusical sounds in his art, such as alarm clocks, whistles, sirens, a section of common garden hose (the black mystery pipes) and even primitive electronic sounds (before such things became commonplace).