A clay court is one of the types of tennis court on which the sport of tennis is played. Clay courts are built on a foundation of crushed stone, brick, shale, and other aggregate, with a thin layer of fine clay particles on top. Clay courts are more common in Continental Europe and Latin America than in North America, Asia-Pacific or Britain. The only Grand Slam tournament that uses clay courts is the French Open.

A tennis court is the venue where the sport of tennis is played. It is a firm rectangular surface with a low net stretched across the centre. The same surface can be used to play both doubles and singles matches. A variety of surfaces can be used to create a tennis court, each with its own characteristics which affect the playing style of the game.