Decken was a French automobile manufacturer that operated from 1901 to 1906, based in Paris. The company, officially known as H. Decken et Compagnie, produced a range of conventional vehicles during its brief existence.

The lineup included four distinct models, featuring a 6 horsepower single-cylinder engine, as well as twin-cylinder variants with outputs of 12 and 16 horsepower. Additionally, the company offered a more powerful 20 horsepower four-cylinder model. The 6 horsepower vehicle was designed with a two-seater body and a spider seat positioned at the rear, while the larger models were equipped with five-seater tonneau bodies.

Despite the production of these vehicles, only one Decken car is known to have survived to the present day. This surviving model is a 6 horsepower vehicle, which is currently owned by a member of the Veteran Car Club in Hampshire, England.