Eighty-three spectators are killed and at least one hundred are injured after an Austin-Healey and a Mercedes-Benz collide at the 24 Hours of Le Mans, the deadliest ever accident in motorsports.

Austin-Healey was a British sports car maker established in 1952 through a joint venture between the Austin division of the British Motor Corporation (BMC) and the Donald Healey Motor Company (Healey), a renowned automotive engineering and design firm. Leonard Lord represented BMC and Donald Healey his firm.

Mercedes-Benz, commonly referred to simply as Mercedes and occasionally as Benz, is a German automotive brand that was founded in 1926. Mercedes-Benz AG is based in Stuttgart, Baden-Württemberg, Germany. Mercedes-Benz AG manufactures luxury vehicles and light commercial vehicles, all branded under the Mercedes-Benz name. From November 2019 onwards, the production of Mercedes-Benz-branded heavy commercial vehicles has been managed by Daimler Truck, which separated from the Mercedes-Benz Group to form an independent entity at the end of 2021.

The 1955 Le Mans disaster was a major crash that occurred on 11 June 1955 during the 24 Hours of Le Mans motor race at Circuit de la Sarthe in Le Mans, Sarthe, France. Large pieces of debris flew into the crowd, killing spectators and French driver Pierre Levegh. It is unknown exactly how many people were killed, but the number is known to be at least 82, and many sources estimate 84 deaths. Regardless of the exact death toll, this crash was the most catastrophic event in motorsport history, prompting multiple countries in Europe to ban motorsports nationwide; Switzerland did not lift its ban until 2022.

Motorsport or motor sport are sporting events, competitions and related activities that primarily involve the use of automobiles, motorcycles, motorboats and powered aircraft. For each of these vehicle types, the more specific terms automobile sport, motorcycle sport, power boating and air sports may be used commonly, or officially by organisers and governing bodies.