Continuity mistake: When MJ and Peter are discussing the beating that Peter gave Flash that morning in school, MJ says, "He's just glad you didn't give him a black eye for graduation." This scene takes place the day after Peter was bitten by the spider, when the weather is cold. High school graduations generally take place in June or late May - so any black eye Peter might have given Flash would long be healed up by graduation. (00:29:15)
Suggested correction: I think it's just figurative speech, exaggeration. He hits him on the chest after all.
Continuity mistake: During the scene where the apartment building is on fire - a woman points directly up and exclaims, "Look up there!" while Spider-Man is still swinging towards the fire from several blocks away. (01:19:00)
Suggested correction: Movie scenes are not always in exact chronological order. A powerful attack getting shown 3 times from different angles for dramatic effect does not mean it happened 3 times. When woman points up, the movie shows Spider-Man approaching starting from a few seconds prior in time to show us some cool swinging action.
Continuity mistake: In the scene where Osbourne tries the performance enhancers on himself, he takes off his labcoat and throws it into a corner. We see a long shot of the lab, and the coat is in at the base of the pillar. In a subsequent long shot however, the coat has moved a foot or so. (00:14:45)
Continuity mistake: During the scene in which Peter is introduced to Norman Osborn in front of the museum, keep an eye on the Volvo parked behind the Rolls Royce. When the camera first faces Mr. Osborn (Willem Dafoe), the Volvo in the background has the window rolled halfway down. Camera switches to Peter and Harry, then back to Mr. Osborn. This time the window is all the way up. When the camera comes back to Mr. Osborn again, there is someone leaning in the window talking to the driver. The next time the camera comes back to Mr. Osborn, the window is again halfway down. (00:05:54)
Continuity mistake: When Uncle Ben's killer enters the warehouse he reloads his gun and pulls the slide back to cock it. Later, when he points the same gun at Peter, you can hear the distinct sound of the hammer being pulled back. However, despite cocking the gun twice, you can see that the gun is not cocked. (00:46:25)
Continuity mistake: When Osborn is getting ready to radiate himself at his laboratory, he drinks the small bottle of anti-coagulant before stepping into the chamber. He then smashes the bottle on the ground to his left. But in later shots you see no evidence of the fragments of the glass bottle. (00:15:35)
Continuity mistake: When Peter runs downstairs the morning after his bite, Uncle Ben is startled from drinking his coffee. From the front angle, Uncle Ben is holding the cup with two hands. When he turns to look at Peter and the angle changes, he's holding the mug with only one hand. (00:19:08)
Continuity mistake: In the final battle scene, Goblin's costume alternates between clean (green) and dirty (white/dusty) throughout the scene. (01:41:30)
Continuity mistake: When Parker is chasing the robber into the abandoned warehouse, you see a shot of the robber holding the gun in his left hand and carrying the money bag in his right hand. However, the next shot you see him load a clip into the gun with the bag in his left hand and the gun in his right hand. (00:45:25)
Continuity mistake: In the scene where Spidey is stopping the armored car robbery, he dispatches several thugs with some fancy, acrobatic fighting. When he lands, a money bag is visible in front of him that wasn't there in the wide shot. (00:58:30)
Continuity mistake: When Osborn awakens in the vault, the position of his hand grabbing the doctor's throat changes positions depending on the angle.
Continuity mistake: At the World Festival, Goblin is beating up the cops; however, when Spider-man tries to punch him, there is a long shot where you can see that there aren't any police anywhere. (01:05:30)
Continuity mistake: Right after Peter has beats up Flash, only Mary-Jane stands to the right of Peter. If you look behind her there are two extras, to the right of her whenever there is a far shot, and to the left of her on the close up of her. (00:25:00)
Continuity mistake: Bone Saw had four valets during the wrestling scene yet during the cage match he's only got three at ringside, one of the two blondes disappears.
Suggested correction: I just loaded up the scene. All four of them are definitely there during the cage match. There's even several shots where you can see all four at the same time.
Continuity mistake: When Spider-Man is being gassed by the Green Goblin, the mouthpiece of the Green Goblin's mask is open, and Osborne's lips are visible moving as he speaks to J. Jonah Jameson. Later in the scene where Spider-Man fights the Green Goblin in the burning building, a close-up of his mask is shown again, but this time there appears to be some kind of black mesh screen in the mouth of his mask.
Suggested correction: It's never fully open, it's just easier to see through the mesh in certain lighting.
Continuity mistake: At the Unity Day Festival, when Goblin says "Impressive!" and kicks Spider-Man away, watch closely. Goblin goes from standing on top of a bare ground to standing on top of some sort-of tarp instantly between cuts as Spider-Man hits the first table.
Continuity mistake: During the World Unity Festival, after the balcony begins to collapse, Mary Jane hits the railing and a support falls from it. The support reappears and stays until she falls.
Continuity mistake: When Mary Jane falls off the balcony she falls sideways except for a shot of her falling face down. Shot changes and she is falling sideways again.
Continuity mistake: When Peter wakes up the day after he was bitten by the spider and goes to the living room doing a little "stunt", Uncle Ben immediately turns to him, but in the next shot he makes a forward movement as Peter falls on the ground after the stunt.
Continuity mistake: When Peter tries his first web swinging on the rooftop, the sky turns from sunny to cloudy between shots.
