Robert O'Brien

Robert O'Brien may refer to:


 * Robert O'Brien (artist) (born 1939), from British Hong Kong
 * Robert O'Brien (canoeist) (born 1933), American sprint canoer
 * Robert O'Brien (cricketer) (1869-1922), Australian cricketer
 * Robert O'Brien (executive) (1907–1997), Hollywood businessman
 * Robert O'Brien (racing driver) (1908–1987), American
 * Robert O'Brien (RAF officer) (active 1990s), former Air Secretary
 * Robert C. O'Brien (born 1966), US National Security Advisor
 * Robert C. O'Brien (author) (1918–1973), US journalist and children's book author
 * Bob O'Brien (born 1949), baseball player
 * Bob O'Brien (basketball) (1927–2008), American basketball player