The Mercedes-Benz 450SEL 6.9 is the high-performance version of the W116 S-Class saloon. It was based on the long-wheelbase version of W116 chassis introduced in 1972 and equipped with Mercedes-Benz M100 V8 engine and full hydropneumatic suspension system. The 450SEL 6.9 was presented to the public at the Geneva Auto Show in 1974 as the successor to the original high-performance saloon from Mercedes-Benz, the 300SEL 6.3 (1968–1972). Like the 300SEL 6.3 before it, the special displacement number (6.9) was affixed to the trunk lid to differentiate itself from the 450SEL. The 450SEL 6.9 was produced in very limited numbers from 1975 to 1981.

The Mercedes-Benz W116 is a series of flagship luxury sedans produced from September 1972 until 1980. The W116 automobiles were the first Mercedes-Benz models to be officially called S-Class, although some earlier sedan models had already been designated unofficially with the letter 'S' for Sonderklasse. The W116 was selected as European Car of the Year in 1974.