The Minus World glitch is believed to be first acknowledged by Nintendo in the third issue of Nintendo Power (November/December, 1988, page 55).

According to Super Mario Bros. Wonder's art director Masanobu Sato, Shigeru Miyamoto reportedly explained during the development of the first Super Mario Bros. that the reason why Goombas damage Mario when walking into them is because they bite Mario on impact. Due to graphical and hardware limitations, this could not be shown at the time. However, while Super Mario Bros. Wonder is thought to be the first game in the mainline series that shows this detail in gameplay, it's not the first game in the overall franchise to show it, as Goombas had been seen biting in earlier spin-off games like Super Mario RPG: Legend of the Seven Stars.

According to Pac-Man creator Toru Iwatani, Pac-Land had a strong influence on the development of Super Mario Bros. In an interview with Geek Culture, Iwatani stated:

According to source code leaked in 2020, during development of Super Mario Bros., Bowser was called "Big tortoice" [sic]

Super Mario Bros. / Duck Hunt / World Class Track Meet has unused graphics from Super Mario Bros: The Lost Levels, which can be activated by a Game Genie code, allowing one to play SMB1 levels with The Lost Levels graphics, albeit with some glitched tiles in different parts of the game.

The concept of Mario riding a dinosaur was first concieved for Super Mario Bros., but was considered impossible from a technical standpoint. Eventually, this concept would be used in Super Mario World with Yoshi.

During the development of Super Mario Bros., a 16x32 pixel square represented the player character. After asking to see sales figures from the head of Nintendo's Sales and Marketing Division, Takashi Tezuka and Shigeru Miyamoto decided to make Mario the game's protagonist due to the success of the Famicom port of Mario Bros.