Richard O'Sullivan (born 1944) is a British actor.
Richard (or Dick) O'Sullivan may also refer to:
- Richard O'Sullivan (filmmaker) (born 1968), American screenwriter, director, actor, producer, cinematographer, film editor, radio personality, and founder of Lost Colony Entertainment
- Richard O'Sullivan (teacher) (1826–1889), teacher and school inspector in Auckland
- Dick O'Sullivan, Irish boy featured on programme five of On the Street Where You Live
- Dick O'Sullivan, interim manager of Punchestown Racecourse