Brian O'Brien may refer to:

• Brian O'Brien (optical physicist) (1898–1992), American optical physicist and the founder of the Air Force Studies Board
• Brian O'Brien (space scientist) (1934–2020), Australian physicist and space scientist
• Brian O'Brien (rugby union) (1939–2023), Irish rugby union player and coach
• Brian O'Brien (journalist) (1922–1982), New Zealand sports journalist and politician
• Clock (character), a fictional crime-figher whose alter ego is Brian O'Brien

See also

• Brian O'Brian, an Italian-American series of television shorts

Topics referred to by the same term

This disambiguation page lists articles about people with the same name.
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