Continuity mistake: When the phone rings, it changes direction when the camera changes. In the same shot, there is a purple book on the table, but in the next shot, it is orange. (00:06:33)
Continuity mistake: When Princess Toadstool feels sorry for Toad, her blue brooch turns yellow, while the yellow border turns blue; and shortly after, it disappears. (00:04:59)
Continuity mistake: In the live action segment, when Mario and Luigi are fixing the pipe, Nicole is holding a newspaper, but when she is sprayed by the water, it disappears. (00:03:29)
Continuity mistake: After Mario drains the dungeon, Toadstool and Toad jump off the shackles they were hanging off. However, when Mario jumps off, Toad is again seen hanging from the shackles even though he had previously jumped down. The next scene confirms this by having him on the ground where he belongs. (00:10:28)
Continuity mistake: When the mother Birdo lands at her house, the chairs at the table have their backrests without cushions, but in the next shot, cushions appear on them. (00:03:45)
Continuity mistake: When first showing the Mushroom Land during the animated intro, there is no path present, but in the next shot, one appears. (00:03:47)
Continuity mistake: When Mario moves a curtain in the animated intro, there is no cavity in the shower, but in the next shot, one appears. (00:03:35)
Continuity mistake: When the magic carpet moves upward after Mario becomes Super Mario, Luigi's visor goes from green to skin colour and back to green.
Continuity mistake: When the limousine drives down the street, it has the US and USSR flags on the front of the limousine, but when water pushes it back, the flags change to generic red and yellow flags. (00:12:19)
Continuity mistake: When the crocodiles approach the general store, the store's front door has its doorknob on the left, but in the next shot, it appears on the right. (00:06:26)
Continuity mistake: When the ketchup lorry crosses the bridge, it has a cream cab and a red trailer, but in the next shot, it has a blue cab and a grey trailer.
The Koopas are Coming! The Koopas are Coming! - S1-E35
Continuity mistake: Just before the pillory is destroyed, it is violet, but in the next shot, it is orange. (00:14:37)
Continuity mistake: This mistake is in the intro with Mario and Luigi in real life. When Mario breaks the ceiling while Bowser is holding a yellow bar, Mario's gloves disappear from his hands when he jumps to break the ceiling. When he lands, his gloves reappear back on his hands. (00:00:26)
Mario meets Koop-Zilla - S1-E28
Continuity mistake: When Mario is eating sushi, he eats it with a fork, but his fork disappears and a spoon appears out of nowhere.
Mario meets Koop-Zilla - S1-E28
Continuity mistake: After when Luigi says "It's an earth shake!" when he flips, his straw hat changes into his green cap in mid-sentence. (00:03:58)
Rolling Down the River - S1-E5
Continuity mistake: When the Koopa Troopas discover that Mario and Luigi cheated, Mario's gloves disappear. (00:05:29)
Rolling Down the River - S1-E5
Continuity mistake: In one shot of Toad being thrown into the dungeon, his blue trousers turn white. (00:04:48)
Rolling Down the River - S1-E5
Continuity mistake: When King Koopa says that he wants to capture the Mario Bros, part of his underbelly changes from yellow to green. (00:03:40)
Robo Koopa - S1-E52
Continuity mistake: When Robo Koopa destroys a building, the black border around his chestplate turns white, like the chestplate. This also occurs when he says that the Mario Bros. cannot help Princess Toadstool and Toad. (00:03:22 - 00:08:34)
Star Koopa - S1-E51
Continuity mistake: When Mario asks if his friends have their seatbelts on, Princess Toadstool's brooch changes from yellow with a blue centre to blue with a yellow centre. (00:12:01)