Killoran was born near Ballymote, County Sligo, Ireland. He is regarded, along with his mentor James Morrison and the great Michael Coleman, as one of the finest exponents of the south Sligo fiddle style in the "golden age" of the ethnic recording industry of the 1920s and 1930s.
In 1925, Killoran emigrated to New York City where he polished his fiddling under Morrison's tutelage and launched his own career as a recording artist and band leader. He made dozens of 78 rpm discs as a soloist, in duets with fellow Sligo fiddler Paddy Sweeney, and as the leader of his "Pride of Erin Orchestra."
Killoran's career continued through the depression and into the 1950s, when he recorded some tracks with Sligo flute player Mike Flynn. On occasion, his band was hired to play on trans-Atlantic liners and Killoran visited Ireland several times. He appeared on Irish radio at least once during these trips and visited both Sligo and his wife's home in Miltown Malbay, Co. Clare.
- Paddy Killoran's Back in Town (Shanachie, 1977), tracks reissued on CD "From Ballymote to Brooklyn" along with tracks from Shanachie's James Morrison LP.
- Unknown. "Paddy Killoran". Gateway to Ireland. Retrieved 5 October 2006.
- Geoff Wallis. "From Ballymote to Brooklyn". Irish Music Review. Retrieved 5 October 2006.