Continuity mistake: When Han tells Lando that he can fly the Millennium Falcon during the battle, when Lando says, "Would you get going, you pirate", his entire outfit is reversed - his shoulder holster strap goes the other way, and his rank insignia changes side too. (00:50:00)
Revealing mistake: After the heroes get snared and surrounded by Ewoks on Endor, the Ewoks mistake C3PO for a god and start bowing. There is one Ewok which only has holes where the eyes and mouth are and you can see the eyes and mouth of the person inside the Ewok costume. (01:07:50)
Continuity mistake: When Leia offers the Ewok food, she holds it out in her left hand, but from a different angle it's in her right. (01:01:15)
Continuity mistake: When Luke is prodded out to 'walk the plank', into the Sarlaac pit, he jumps off the board and springs himself back up. If you watch this carefully, you can see that only one hand catches the board and that just by the fingertips, but in the next shot both hands are springing him upwards. (00:31:20)
Revealing mistake: When Han is running from the explosion of the shield generator on Endor, you can see his reflection in the plexiglass that is used to protect the camera from the explosion. Since the reflection isn't of Han's back, the plexiglass must be in front of him. (01:49:55)
Continuity mistake: When Lando is hanging over the pit, he has gloves on, then he has no gloves, then they're back and so on.
Continuity mistake: When Jabba pulls Leia's chain, there is a long shot as she leaps up onto his throne, and he is holding his wine goblet in his left hand, and pulling her chain with his right. However, in the very next shot (in which he says "Soon you will learn to appreciate me"), the entire frame is reversed. This is evident in Jabba's holding the wine in his "right" hand, his higher-placed nostril (which is normally on the left on his face) is now on the "right," Leia's reversal of her armlet, etc. (00:29:20)
Continuity mistake: Widescreen version: When Darth Vader dies, the chin part of his helmet is missing in the last shot. (02:01:30)
Trivia: In frame by frames views of the scene where Vader lifts the Emperor and throws him down the shaft you can see x-rays of Darth Vader.
Continuity mistake: When Vader ignites Luke's lightsaber, Luke is standing next to a column. When Vader extinguishes the lightsaber, Luke is standing further away from the column. In the next shot, he is standing next to it again. This is best seen in the widescreen version. (01:21:10)
Revealing mistake: When 3PO and R2 are being assigned to their droidly duties in Jabba's palace, there is a shot of a poor droid having hot irons branding his feet. The irons are never closer than an inch from the droid's feet, and the steam that allegedly comes from the burning is obviously being shot out of holes in the droid's feet.
Continuity mistake: When Vader's shuttle is approaching the Death Star, the crew in the control room of the Death Star are wearing black gloves. One of them then reaches forward to press a button, but in the close-up of his hand pressing the button, the hand is not wearing gloves at all. This can only be seen in the widescreen version. (00:02:25)
Continuity mistake: After Vader's shuttle lands on Endor, as the AT-AT is walking towards one of the ramps, you can see that the ramps are connected right next to the lift, under the landing pad. But when Vader exits the lift, there's a circular platform going around the lift, which wasn't there in the previous shots. (01:19:40)
Revealing mistake: When Luke is fighting on a skiff, he kicks one of Jabba's men in the head, causing him to fall off. Luke's foot doesn't make any contact with the person. (00:33:48)
Revealing mistake: Widescreen version only: After Luke cuts off Vader's hand, the Emperor says, "Now, fulfill your destiny, and take your father's place at my side." In the next shot, Luke's lightsaber blade goes through the railing, without damaging it. (01:49:15)
Revealing mistake: Just before Luke chops off Darth Vader's hand in the battle at the end of the movie, you can see that the bar has already been cut (the line is visible) to give the illusion that Luke cut through the steel bar with his lightsaber as well as Vader's hand. (01:48:45)
Continuity mistake: When Lando says, "Fighters coming in," a whole bunch of TIE fighters come towards them. There's initially a lot anyway, but then after about a second, two horizontal lines of 4 fighters appear from nowhere (centre screen, underneath the Super Star Destroyer). They suddenly just pop into existence, large enough that we should have seen them approaching. (01:31:20)
Continuity mistake: In the scene where Luke and the others are trapped in the net, the dead animal changes appearance (both injuries and actual appearance) and position several times. For example, the animal seen when they are in the net has a different mouth and a bigger area of white fur from the one seen a few shots earlier. (01:08:35)
Revealing mistake: In the wide-shot where Luke leaps from the prisoner skiff over to another skiff, you can see the stick used during the filming, which is much shorter than the regular one. The blade is not even glowing. (It is not just simply the hilt of the sabre, it's too long for that.). (00:32:15)
Continuity mistake: When Luke is riding the speeder bike against the trooper, the black glove on his right hand jumps to his left and then back again. (01:01:15)