Continuity: In the scene where Peter is riding his scooter to Mary Jane's play, after the music fades out you see a black convertible being chased by several police cars. The black convertible is rammed forcibly, and you see many hideous dents on the side of the car. Thirty seconds later, after Peter is done talking to the kids, we see the same car from the same side it got rammed into, but the hideous dents have vanished.

Continuity: Peter has a small horseshoe-shaped scar on his right cheek. In Dr. Octopus's lab, as Octopus is destroying the fusion reactor, they share a meaningful look and the scar has switched cheeks.

Plot hole: At the end, when Peter saves Mary Jane from the collapsing structure, he jumps up in the air and swings her to safety. However if you look at the web he is holding onto it is hanging down vertically. What did he attach the web to that was directly above him, the sky? Every bit of the structure around him was/had collapsed and the only thing remotely close to swing from was the cranes. Yet we see that was quite a distance away, so Peter would have had to shoot the web away from himself not above him.

Continuity: As Peter stops the elevated train with many webs, a tear appears in his suit on the inside left arm during a closeup. Later, when his arms are still outstreched, there are many shots where you can see that the tear has disappeared; for example, a few shots later when he is still trying to stop the train; when the passengers are lifting him over their heads into the train; and many others.

Continuity: At the end of the "I've changed" conversation with Mary Jane, the taxi is right next to her as she turns towards it (you can see its roof next to her face), yet in the very next shot she has to cross the street to get to it.

Continuity: During the train scene, Spider-Man's mask had gone partially black. We also see it when Spidey puts his mask back on. Yet when Doc brings him to Harry, we don't even see a patch of darkness on his mask.

Visible crew/equipment: On the way to the theater Peter intercepts a police officer chasing a couple of criminals. At the end of that scene one of the police cars has a tremendous wreck that swings the car sideways. There is a clear shot of the driver with a black helmet on.

Continuity: When Aunt May hugs Peter near her "hero" speech, she hugs him with her head to his left shoulder. The shot changes and you see that she is now on Peter's right shoulder. The shot changes back and you see her on his left shoulder again.

Revealing: In the scene where Peter saves the child (Venus Lam) from the burning building, right after the jump over the floor opening, the child stands up to help Peter we can see she wears knee pads under her pajamas.

Trivia: "The Punisher" has a small cameo in Spider-Man 2. At the end when Mary Jane is running through the park with her wedding dress on, Thomas Jane can be seen glancing at her while she runs past. (He is not in any kind of costume, but it is Jane nonetheless.)