Robert O'Brien (April 11, 1908 – February 10, 1987)[1] was a racing driver from the United States.

He mostly raced sports cars in the US, finishing fourth in the 1952 12 Hours of Sebring in a Ferrari 166 MM shared with Richard Cicurel.

[1] This included an appearance at the 1952 Belgian Grand Prix driving a Simca-Gordini T15 at Spa-Francorchamps.

[2] He subsequently drove (and retired) the same car in a race at the Grenzlandring in Germany before returning to the US.

[2][3] O'Brien is one of the more obscure drivers to have participated in the Formula One World Championship, and unsubstantiated rumours arose that he was involved with the CIA and operated as a spy.