If Boom Boom is defeated with a Starman, the "?" Orb that appears afterwards will spawn upside-down, and in the center of the arena.

In the initial Japanese release, getting hit in any form other than small Mario would revert Mario back to his small form. This was changed in the western release so that getting hit as Fire Mario or any of the suit power-ups reverted Mario back to Super Mario. This was carried on in every platformer Mario game released after Super Mario Bros. 3, with the exception of the original SNES release of Super Mario World.

In the SNES and GBA remakes of the game (Super Mario All-Stars and Super Mario Advance 4), the creatures the Mushroom kings were transformed into were changed from regular animals, such as a dog or a spider, to creatures specific to the Mario series that don't otherwise appear within Super Mario Bros. 3.

The king will give a different message than normal if Mario beats an airship wearing either the Frog Suit, the Tanooki Suit, or the Hammer Suit. The King will mistakenly believe that Mario has been transformed into a frog if he is wearing the Frog Suit, believe Mario is an actual raccoon if he's wearing the Tanooki Suit, and if Mario is wearing the Hammer Suit, he'll ask to borrow Mario's clothes.

Entering stage 5-3 with a Tanooki Suit and dropping into a Kuribo's Shoe while Statue Mario will grant the player total invincibility from enemies through the remainder of the level.

If a Muncher is hit with Raccoon Mario's tail attack, it will turn into a block. This trick carried over to the Super Mario All-Stars version, but not the GBA version, Super Mario Advance 4: Super Mario Bros. 3.

Inside the game's data are two unused Mario sprites that looks almost identical to the final release, but his overalls are colored pink rather than blue.

World 4 (Giant Land) is shaped like a Koopa Troopa.

Over 30 new levels were created for the Game Boy Advance release of the game, Super Mario Advance 4: Super Mario Bros 3. In order to access these new levels, the player requires an e-Reader for Game Boy Advance and the various e-Reader Level Cards. To transfer the levels, the player would require 2 Game Boy Advance systems, the e-Reader, a link cable, and a copy of the game. Because of this, these levels have mostly fallen into obscurity.

Only 10 Level Cards were released in North America, while the other 20 Level Cards were released in Japan.

When the game was re-released on the Wii U Virtual Console and Nintendo Switch Online, all 38 e-Reader levels were unlocked by default as the e-Reader was only supported for the Game Boy Advance.

If the player tries to make Mario slide while wearing a Hammer Suit, Mario will go into the suit's shell. However, if Mario obtains the Hammer Suit while sliding, an animation of Mario sliding while wearing the Hammer Suit is used. This is the only time this animation can ever be seen.

In a 1996 interview with Shigeru Miyamoto published in Super Mario 64's first Japanese strategy guides, he revealed that Mario's running animation, speed and movements in that game were influenced by Arale, the main protagonist of the 1980 Akira Toriyama manga/anime "Dr. Slump":


However, Dr. Slump's influence throughout the Mario series could trace back even further. Some particular examples from Mario games include:

• His running speed, animation, the Racoon and Tanooki Suits from Super Mario Bros. 3
• The Wing Cap from Super Mario 64
• The Cat Suit from Super Mario 3D World

Even traits of Mario's happy cartoonish personality, his short stature and gloves, and blue-red-overalls color scheme bear enough similarities that they all could have been taken from Arale's appearances and other elements throughout Dr. Slump. Despite this, outside of Miyamoto's comment, these connections are not known to have been elaborated on by any other employee from Nintendo.

Many international Mario fans were confused by the design of the Angry Sun in the New Super Mario Bros. U style of Super Mario Maker 2, noticing how it appeared more stern than angry. This is due to the fact that "angry" is not part of the enemy's name in Japan, just being called "sun", meaning that anger is not an inherent part of the character and giving it a different expression would make more sense without knowledge of its localized name.

The new design of the "Angry" Sun seems to be based on pre-colonial mythology based on the sun, most particularly the Inca sun god Inti, a design inspiration that seems to exist in anthropomoprhic suns from multiple other Nintendo games such as The Legend of Zelda: Ocarina of Time, Mole Mania, and Kid Icarus: Of Myths and Monsters

In World 8, it's possible to bypass almost the entire battleship level by dropping into the water and swimming beneath the ship, jumping back on once the autoscroll reaches the vessel's stern. In the international version of the original NES release, one tile is removed from the rightmost portion of the ship in order to make the final jump easier.