Continuity mistake: When the little Ewok finds Leia, and she rises up, he points his spear at her and you can see that the front of his leather hood is over the spear's shaft. The shot changes to Leia, the back to the Ewok and now spear is over the hood, the shots change again and now the hood's front is crumbled up between the spear and the Ewok´s body.
Continuity mistake: After Vader enters the Emperor's throne room to tell him that Luke is one of the Rebels landing on Endor, as the shot ends, he is just about to walk up the stairs. In the next shot, he has already walked up the stairs. (01:03:50)
Continuity mistake: When Vader is searching for Luke in the dark, in the first shot, he is walking around a computer terminal, with the great window behind him. In the next shot, he's on the other side of the terminal, with the window in front of him. (01:47:10)
Continuity mistake: Before the Emperor gives permission to fire the Death Star, in the scene at the bridge of the Star Destroyer, the blue rank insignia of Admiral Piett and another Imperial officer is coloured black. This is probably caused by bluescreen effects replacing everything blue with the colour of space. This can also be seen when a Rebel ship hits the Star Destroyer at the end of the film.
Continuity mistake: In the beginning of the scene where Luke is being electrocuted by the Emperor, the Emperor is standing at the bottom of the stairs. When he says, "Young fool... Only now, at the end, do you understand", he is standing in front of the great window. However, in the next shot of the Emperor, he is standing at the bottom of the stairs again, before he walks down to his previous position. (01:50:50)
Continuity mistake: When Green Leader's starship crashes into the Star Destroyer, Admiral Piett begins to run away. As the shot ends, he is about one meter away from the window. In the next shot, he is several meters away from it. He couldn't have moved that quickly between shots. (01:54:20)
Continuity mistake: In one scene of the battle of Endor, Chewbacca is accompanied by 2 Ewoks while pursuing one of the ATSTs. However soon after their first appearance, one of the Ewoks' costume looks completely different from the original one.
Continuity mistake: When Luke is to be executed, he walks to the edge of the plank, and his feet are side by side as he stops walking. But in the beginning of the next shot, one of his feet is behind the other and we see him take another step. (00:30:55)
Continuity mistake: As we follow Fett's flight after being hit by Han, we cut to a scene showing the front half of a skiff. Luke then kicks one of Jabba's henchman. He very clearly misses the man by a few inches, yet the man still tumbles to his doom nonetheless.
Continuity mistake: When Han, Luke and Chewbacca are sentenced to death, there's a strange alien with a long tongue hanging from the ceiling, in the upper, left hand corner. In some shots, the creature is moving, in other shots, it is completely still and appears to be asleep or something.
Continuity mistake: After Luke kills the Rancour, Jabba says, "Bring me Solo and the Wookiee", and Lando is nowhere to be seen. In the next shot, he is suddenly standing in front of Jabba's platform, and some of the other people have changed position. (00:27:00)
Continuity mistake: In the scene on Endor where Luke and the Stormtrooper are duelling on the speeder bikes. The glove on Luke's damaged hand changes sides between the front and side on shots.
Continuity mistake: This is a 'Special Edition' error only. After the scene in Jabba's palace when R2D2 and C3P0 are assigned their 'duties' we see the audience chamber in their party, and Jabba holding his dancing girl's leash. When the first song ends, Jabba says 'Do that again' and his hands are empty. When next he's shown, the leash is back in his hands.
Continuity mistake: At the very end of Palpatine and Vader's conversation, we are tight on the Emperor. He is walking past a series of grey suited officers. But when we instantly cut to a wide angle shot, they are now in front of rows of stormtroopers.
Continuity mistake: Widescreen version: When the captured rebels are led out of the bunker, C-3PO walks out from behind a tree. In the next shot, the tree is much bigger, and C-3PO is further away from it. (01:33:10)
Continuity mistake: When the droids enter Jabba's throne room, in the shot facing the droids, they are not standing on the same part of the floor as in the previous shot. Also, R2-D2 is facing Jabba, but in the previous shot, he was facing C-3PO. (00:08:15)