Revealing mistake: When Darth Vader and Ben are fighting, Darth's chestplate is on backwards and the belt "buckle" is as well. It appears that the entire shot was reversed.
Revealing mistake: On the Jawas' transporter, when R2D2 looks around in one of the shots, you can very clearly see the actor, Kenny Baker, inside through his eye hole.
Revealing mistake: In the scene at the end of the very first battle, where Imperial troops have just taken control of Princess Leia's rebel ship, Darth Vader breaks the neck of the rebel leader and tosses his body to the wall. The "dead" rebel puts up both of his hands to avoid slamming his face into the wall.
Visible crew/equipment: Just after the Falcon takes off from Mos Eisley, there's a shot of the Falcon with Star Destroyers chasing. The next shot is of Han Solo alone in the cockpit. Watch carefully behind him in the doorway, and you'll see the shoulder of a man in a green shirt quickly move out of shot.
Revealing mistake: When the Tusken Raiders are seen raiding Luke's speeder, you can actually see the wheels or at least whatever is holding it up off the ground.
Continuity mistake: After Luke gets pulled underwater in the trash compactor, he is shown with a piece of garbage on his forehead in one shot. In the next shot his forehead is clean, but in the following shot, the piece of garbage is back again.
Continuity mistake: When Obi-wan and Luke are watching the hologram of Princess Leia projected onto a small table, the objects on the table change position and number in each shot.
Continuity mistake: In the scene where Luke and Leia are about to swing across the canyon inside the Death Star, Leia shoots one last time. She hits the bulkhead behind the stormtrooper on the right and he falls forward. The trooper on the left continues firing (as seen in the screencap).
Visible crew/equipment: In the original widescreen version, during a long shot of a loading bay in the Death Star, you can see a crew member walk just into shot on one side of the screen, stop, look up, and back out again.
Revealing mistake: When an Imperial Officer is running down the tunnel in the Detention Block towards Han, Luke and Chewbacca, Han clearly shoots the top-left hand corner of the tunnel and the Imperial Officer falls down the stairs as if he shot him.
Revealing mistake: In the Death Star corridor leading to the Millennium Falcon, just before Han says "Didn't we just leave this party?" you can see Carrie Fisher and Mark Hamill's shadows on the wall as they await their cue to run in.
Visible crew/equipment: When C-3PO is on the Conveyor belt in the Jawas transport vehicle, if you look in the reflection in his head you can see the camera crew.
Continuity mistake: After the Stormtrooper tells Darth Vader the Death Star plans are not in the main computer, when Vader lifts the Rebel off his feet by his throat as the Rebel tells him they intercepted no transmissions, take note of the leg plates on the Stormtrooper to Vader's right. In the wideshot, the Stormtrooper's left leg armor does not have the knee protector plate (it looks as if it's at his right knee because the extra switched them), but in the next closeup the knee plate appears at his left knee, as it should be.
Revealing mistake: Just before Lord Vader appears the first time (on the boarded consular ship, through the breached door), there is a Stormtrooper checking another trooper apparently dead on the floor (he's lifting the dead one's head). Then Vader enters, and the Stormtrooper quickly straightens up, dropping the head. It turns out the "dead" Stormtrooper was actually alive, however, because he carefully lowers his own head to the floor.
Revealing mistake: Sand people are up on a hill overlooking a valley below where Luke is passing by in his speeder. One of the sand people takes aim at Luke, but his companion stops him. Right before the end of the shot, as the speeder is traveling towards the lower right corner of the screen, it becomes transparent. This is a multiple exposure shot, and the path of the speeder wasn't quite lined-up right.
Continuity mistake: The first interior shot of the Millennium Falcon's cockpit shows small hanging dice. In every other shot, however, the dice are gone.
Visible crew/equipment: When the Falcon is in the Death Star hangar, a scanning crew is sent aboard to find passengers, one of the stormtroopers walks straight past the camera and its shadow is visible on his leg.
Audio problem: When Vader is talking to an Imperial officer in the hangar in the Death Star, when the officer says, "It must be a decoy, sir. Several of the escape pods have been jettisoned." his head is shown from behind, but his profile shows his mouth is moving before the words are heard.
Continuity mistake: After Darth Vader kills Ben, there's a shot from the docking bay towards him. Vader's lightsaber is missing its red color. [This has been fixed in the 2004 DVD, but is still valid for VHS prints.]
Continuity mistake: When Leia shoots a hole in the detention area wall for their escape, the hole is not big enough to jump through, but when they all jump in, the hole is much bigger.
Continuity mistake: After Darth Vader has killed Obi-Wan and walks towards the group of storm troopers onto the Millennium Falcon, Luke shoots the dock door control, successfully closing it, fully blocking Vader's path. In the shot immediately following the door is closing once again.
Revealing mistake: In the scene where the "torture" robot goes to get information from the princess, if you look carefully on the side of the syringe you will read monoject, which is an American hypodermic syringe manufacturer.
Revealing mistake: You can see the arm of the crane used to lower the torture device through the door when it is going into Leia's room.
Revealing mistake: When Darth Vader flies out of the Death Star you see the light falling on the back of the ship change as he clears the bay. Later, when he regains control of his spinning fighter the same shot with the falling shadow is used to show him flying away.
Continuity mistake: Special Edition DVD. When Luke, Obi-Wan and droids arrive at space bar in Mos Eisley, notice the herder with white jacket followed by dinosaur-creature on a leash and then the R2 unit. In the next shot dinosaur and R2 are there, but the herder has disappeared.