Super Mario Bros. is a platform video game developed and published by Nintendo for the Nintendo Entertainment System home console. Released as a successor to the 1983 game Mario Bros., Super Mario Bros. was released in Japan and North America in 1985, and in Europe and Australia two years later. In Super Mario Bros., the player controls Mario and his brother, Luigi, as they travel through the Mushroom Kingdom in order to rescue Princess Toadstool from the antagonist, Bowser.

Super Mario Bros. was critically acclaimed. In 2005, a poll by IGN named the "pioneering" and "highly influential" title as the "greatest game of all time", considering it to have aided in resurrecting the crashed American video game market of the 1980s. The game's mid-1980s release served to further popularize the side-scrolling subgenre of the already popular platform video game genre of the early 1980s.

In addition to its definitive features, the game has also sold well, and was the best-selling game of all time for a single platform for approximately three decades until it was surpassed in the late 2000s by Nintendo's Wii Sports, selling over 40 million units and becoming one of the defining titles of the NES. The commercial success of Super Mario Bros. went on to spawn a successful video game series, producing several sequels and spin-off series. The game has been ported to several other Nintendo consoles, including the Super Nintendo Entertainment System and the Game Boy Color, and has also been rereleased for several systems such as the Wii and the Nintendo 3DS as a part of Nintendo's Virtual Console line. Nintendo released special red variants of the Wii and Nintendo DSi XL consoles in re-packaged, Mario-themed limited edition bundles in late 2010 as part of the 25th anniversary of the game's original release. The game's success led to an expansive franchise, receiving a television series, an anime film, and a full-length feature film.