The 1978 Argentine Grand Prix was a Formula One motor race held on 15 January 1978 at Buenos Aires.

The 52-lap race was won from pole position by American driver Mario Andretti, driving a Lotus-Ford, with Austrian Niki Lauda second in a Brabham-Alfa Romeo and Frenchman Patrick Depailler third in a Tyrrell-Ford.

The start was uneventful, with Andretti and Reutemann easily keeping first and second, with John Watson in the Brabham taking third from Peterson.

Reutemann ran third for a while, but then began to drop down the order, and so reigning world champion Niki Lauda took third in his Brabham, which became second with ten laps left when Watson's engine blew up.

Andretti motored on to a crushing victory, with Lauda second and Patrick Depailler's Tyrrell taking the final spot on the podium ahead of James Hunt in the leading McLaren, Ronnie Peterson in the other Lotus and Patrick Tambay in the other McLaren.