Continuity mistake: The head of Mega-Maid mysteriously shrinks in size. After Spaceball-1 transforms into Mega-Maid, the head is gigantic enough for a Winnebago to fly through for a considerable length of time. However, later on in the film, after the head has been jettisoned and crashed on a beach, the head is only big enough to hold a few dozen people. This can be determined by the size of the people coming out of her nose.
Other mistake: When Yogurt comes out of his statue the camera zooms in and the door starts to close, but when the camera zooms out the door starts back and closes again.
Revealing mistake: When we see Dark Helmets' hoverjeep in the desert, watch the front end: you can clearly make out the edge of the mirrored box they used for the "hover" effect.
Deliberate mistake: There is a shot of the huge Yogurt statue that is in slow motion. You can see that the smoke from the statue is rising slower than it normally would. This was obviously done to make the shot longer for Mel Brooks' voice over to fit.
Revealing mistake: When the "Alien" is dancing along the bar, it kicks it's legs. As it dances past Barf and Lone Starr in close up, its legs are stationary and the whole model is bouncing. On cut back to its disappearance through the "stage door", its legs are kicking again. This also applies to the other animations of the "Alien".
Continuity mistake: Lone Starr loses the Schwartz ring during the combat near the self destruct button. However we can see it on his right hand in the shot in the Winnebago after the Mega Maid explodes.
Continuity mistake: While Dark Helmet is tasting the jam that he got off the radar screen, the black man puts his hand over his mouth. But in the next shot of the black man's face his hand has disappeared.
Continuity mistake: In the opening crawl, the letters are capitalized normally. However, in the scene where they are fast-forwarding through it, the opening crawl is in all capital letters.
Continuity mistake: When Lone Starr and Barf watch Spaceball 1 fly away in the desert, the glare on them is red but when you see the engines of Spaceball 1, they are blue.
Visible crew/equipment: After Dark Helmet drops Lone Starr's ring into the vent and Lone Starr tries to retrieve it there is a quick shot of Lone Starr getting up and backing up against the wall. If you look closely you can tell that it is a stunt double.
Continuity mistake: In the scene where Lone Starr is lifting the Yogurt statue with the Schwartz, when Barf walks in, Lone Starr drops his hand. But in the next shot when the statue falls, Lone Starr is still holding his hand up until the statue actually falls and then he drops his hand again.
Continuity mistake: When Yogurt is looking at Lone Starr's medallion in the far away shot, his fingers are around the medallion. When it shows the close-up, he's holding it by the top with two fingers. When it goes back to the far away shot, his fingers are around it again.
Continuity mistake: When Princess Vespa's Mercedes is being pulled into Spaceball one, the speed and position of the Mercedes changes.
Audio problem: When Princess Vespa comes out of Yogurt's tunnel, she says, "Daddy, is it really you?" but her lips don't move.
Other mistake: When Dark Helmet kills the crew member, he chops straight down the man's right side, but the slash mark shows a right-to-left downward slice.