Mario Kart: Double Dash!! is a racing game developed by Nintendo Entertainment Analysis & Development and published by Nintendo for the GameCube (GCN) in 2003. The game is the fourth installment in the Mario Kart series and the third for home consoles after Mario Kart 64.

Similar to the previous titles, Double Dash challenges Mario series player characters to race against each other on Mario-themed tracks. The game introduced a number of new gameplay features, such as supporting co-op gameplay with two riders per kart. One player drives the kart, and the other uses items. It is the first game in the series to use 3D polygon graphics for the racers, as opposed to sprites. Players can switch at any time. Double Dash is the only game in the Mario Kart series to allow cooperative gameplay so far. Double Dash supports LAN play using the Nintendo GameCube Broadband Adapter, allowing up to 16 players to compete simultaneously. There are 20 characters to select from in total, each of which with a special item, and with eleven characters being new to the series.

Double Dash received positive reviews from critics; it attained an aggregated score of 87 out of 100 on Metacritic. Reviewers praised the graphics, new gameplay features, character and item rosters, arcade aesthetic and track design, but elements of the voice acting were poorly received. It is the second best-selling GameCube game of all-time.