Factual error: In the scene in the glass elevator, when Mike Teavee wants to push a button, he presses the TV Room button. The elevator stops going down and immediately moves horizontally. The characters within the elevator are thrown against the wall from the sudden change. However, they are thrown against the wall that is in the direction the elevator is now moving, instead of the opposite wall as they should have been. (01:20:15)
Other mistake: In the beginning of the song about Augustus Gloop, computer generated Oompa Loompas can be seen running through the Chocolate Room, preparing to sing their song. In the DVD release, some Oompa Loompas can be seen running to places that no real person could possibly stand on. This mistake was later corrected in the Blu-Ray release.
Continuity mistake: In the scene where Mike Teavee has smashed up the red pumpkin-looking thing, he smashes it cleanly into two or three quite big pieces. When his father says "Mike, please" the pieces behind him are much smaller and all over. (00:41:35)
Continuity mistake: During Mike Teavee's scene, his father has some bits of hair overlapping the arms of his glasses. On the right side the bits appear and disappear from shot to shot.
Factual error: In the scene where Wonka is flashing back to his childhood, he finds a chocolate that fell beneath the fire grate in the ash. He opens it and eats it unscathed. Knowing that chocolate can melt around even the slightest heat, there is no way the candy would have survived the heat from the fireplace being just inches away.
Revealing mistake: When Augustus is leaving the factory, he is wearing a brown colored glove on the hand he gnaws on. You can see the seams in the glove.
Continuity mistake: At the nut factory, when Mr. Salt is there with the ladies, and he is walking up to the podium, the microphone is facing towards where he is walking from. Then in the next shot when he is at the podium facing the ladies, the mic changes direction and is centered, facing him.
Continuity mistake: When Veruca is choosing a squirrel, she heads for the last one in line, furthest from the ladder. Then after it cuts away and back, she is headed towards the middle of the line, but then she is headed for the last one again. When the squirrels jump her, she is about 1/4 of the way down the line, starting from the ladder.
Continuity mistake: When in the Chocolate Room, Mike Teavee crushes the pumpkin into three pieces. It then zooms out and shows him crushing it into three pieces again when Mr. Teavee comes up.
Continuity mistake: When the factory gates open for the contest winners, the shadows in the courtyard change between shots. [This is a reference to the first film in which the shadows shift a lot. It is also shown in other parodies of the original film, eg, the Family guy episode "Wasted talent". Still a valid mistake.]
Other mistake: When seen from inside the trash chute in the nut sorting room, the Oompa Loompas could not have leaned over the hole as far as they did. Other views during the same scene show they had to stay back a fair distance due to the curve in the floor. (01:15:05)
Factual error: In the scene where Augustus Gloop gets stuck in the pipe from the chocolate river, there are two shots that show the pressure in the pipe is too great and one of the seals of the pipe burst out some chocolate. This could not happen because the machine on the ceiling sucks the chocolate up. In order for the pressure to build up underneath Augustus for the seals to burst there would need to be a machine in the river pushing the chocolate up.
Plot hole: In the end of the movie, when Willy Wonka decides to visit his father, his father does not recognize him until he looks at his "rare teeth." But the wall of newspaper printings that Charlie was looking at included a recent enough picture of Willy that the father would have definitely recognized him, before seeing his teeth, as Willy doesn't look like a normal person with that outfit.