Patrick John O'Hearn (born September 6, 1954) is an American multi-instrumentalist, composer, and recording artist.

Known primarily as a bass guitarist and keyboardist, O'Hearn came to prominence with Frank Zappa and co-founded the early 1980s new wave band Missing Persons with several other veterans from Zappa's bands. O'Hearn's musical repertoire spans a diverse range including new-age. In addition to solo albums, he has composed soundtracks for movies and television.