The Citroën C4 is a car produced under their Citroën marque, from the French automaker PSA Group, and later Stellantis. It was positioned to be the successor to the Citroën Xsara. The first generation production started in September 2004. For its first two generations, the C4 was a compact car/small family car, but it has been redesigned as a subcompact crossover SUV for its third generation.

The Citroën C4 SpaceTourer, also spelled Citroen C4 SpaceTourer in some other languages, is a five-seater car produced by French manufacturer Citroën with a seven-seater version called the Grand C4 SpaceTourer also available. It has a five-door compact multi-purpose vehicle (MPV) bodystyle. The seven seat Grand C4 Picasso made its debut first, at the Paris Motor Show in September 2006, with the five seat version following in January 2007.