The 2003 United States Grand Prix was a Formula One motor race held on September 28, 2003 at the Indianapolis Motor Speedway in Speedway, Indiana. It was the fifteenth and penultimate race of the 2003 Formula One World Championship.

Ferrari's Michael Schumacher won the race after starting seventh. McLaren's Kimi Räikkönen finished second from a pole position start, with Sauber's Heinz-Harald Frentzen third, his first podium finish in three years and his last.

Räikkönen began from pole position after setting the fastest qualifying lap in the second qualifying session. He led for the first 18 laps before making a pit stop for rain tyres due to changing weather conditions. Six different drivers shared the race lead throughout the race due to changing weather conditions. Michael Schumacher overtook British American Racing(BAR) driver Jenson Button to take the lead on lap 38, holding it for the rest of the race to claim his sixth victory of the season and the 70th of his career.