The 2003 Brickyard 400, the 10th running of the event, was a NASCAR Winston Cup Series race held on August 3, 2003 at Indianapolis Motor Speedway in Speedway, Indiana. Contested at 160 laps on the 2.5 mile (4.023 km) speedway, it was the twenty-first race of the 2003 NASCAR Winston Cup Series season. Kevin Harvick of Richard Childress Racing won the race.

Kevin Harvick became the first driver to win the race from the pole position.

The Indianapolis Motor Speedway, located in Speedway, Indiana, (an enclave suburb of Indianapolis) in the United States, is the home of the Indianapolis 500 and the Brickyard 400. It is located on the corner of 16th Street and Georgetown Road, approximately six miles (10 km) west of Downtown Indianapolis. It is a four-turn rectangular-oval track that is 2.5 miles (4.023 km) long. The track's turns are banked at 9 degrees, while the front stretch, the location of the finish line, has no banking. The back stretch, opposite of the front, also has a zero degree banking. The racetrack has seats for more than 250,000 spectators.

• Time of race: 2:58:22
• Average Speed: 134.554 miles per hour (216.544 km/h)
• Pole Speed: 184.343
• Cautions: 5 for 25 laps
• Margin of Victory: 2.758 sec
• Lead changes: 17
• Percent of race run under caution: 15.6%
• Average green flag run: 22.5 laps