Continuity: The apparent size of Kong changes from 6m to 20m. This was a conscious decision of director Merian C. Cooper, who felt that Kong's size wasn't impressive enough in New York.
Revealing mistakes: A Skull Island resident jumps from a hut and falls beside a domed chicken cage, which then hinges backwards and catches the actor's wig, taking it off his head, and remaining on top of the cage.
Plot holes: If Kong was able to climb to the top of the Empire State Building, what prevented him from climbing over the wall on Skull Island?
Continuity: When Kong escapes from his bonds in the theater in New York, he leaves the right cuff of his shackles on his wrist. During the subsequent rampage through the city, the cuff is missing in several scattered shots, and in the entirety of the sequence in which Kong destroys the elevated train. That sequence was reportedly conceived, designed, and filmed when the picture came from the editing room at thirteen reels in length, to which producer-director Merian C. Cooper objected superstitiously. It is easy to see how the cuff would be forgotten in such a situation, but the other disappearances remain a mystery.
Revealing mistakes: When Kong puts Ann on the tree throne (just before the T-Rex encounter), she moves a meter or so to the left as stop-motion gives way to live-action. Also, because of the full-size tree and actress matted over a portion of the miniature jungle set, part of Kong's paw disappears, seemingly behind the tree but, in fact, behind the matted-in live-action at this moment.
Factual errors: When Kong is on the Empire State Building, even though it is supposed to be morning, rays of sunlight are poking through the clouds from the west, on the New Jersey side of Manhattan, an impossibility at that time of day.
Revealing mistakes: When Kong is looking at Ann when she is tied to the sacrificial altar, the pillars of the model altar cast shadows on his chest, but there is no shadow of Ann between them.
Continuity: The first Skull Island native that Kong bites after he breaks through the wall changes orientation between the long shot of him being picked up and the close-up in Kong's mouth. The head changes direction between shots.
Crew or equipment visible: When Kong takes Ann to the edge of the cliff on Skull Island, the animation stand is visible for one frame, left in the shot for a single frame by the technical artists.
Revealing mistakes: In the middle of Kong's battle with the T-Rex, the tree on which Ann Darrow sits falls to the ground. While this occurs, the stop-motion animation of the two fighting monsters ceases completely and visibly before the end of the wide shot of the falling tree.
Continuity: When Kong is shaking the sailors off the log, the second person falls and land at the bottom of the chasm, but when the camera cuts back, he appears to be back on the log.
Continuity: In the wide shot of Kong climbing the Empire State Building, he is climbing the western face of the structure. The financial district is visible to the south in the background. The shot of him atop the tower shows the Chrysler Building directing behind him. That building being to the ESB's north east, that puts Kong on the southern face of the building. When he falls, in the closer shot, he falls back to the south east. Back in the wide shot, he falls off the western side.
Continuity: The head of the full size Kong is more elongated than the close-up head.
Continuity: In close-ups of his face, King Kong has more teeth than he does when his whole body is shown.
Continuity: When Kong is fighting the miniature biplanes the length of the lower wings are the same as the upper. When actual footage of biplanes are used the lower wingspans are shorter than the upper.
Continuity: When Kong tears Ann's dress, he leaves her left shoulder completely bare. After this, there is a string-like strap over it in all shots of her in the rest of the jungle sequence.
Revealing mistakes: As Kong puts Ann down atop the Empire State Building, a matte shot of the live actress replaces the animated model of Ann in Kong's paw, but the matte plainly cuts off a large corner of the shadow thrown by the paw on the building. The same error happens again a few minutes later.
Revealing mistakes: When Kong breaks through the gate on Skull Island, you can see where footage of the wall has "bled" through Kong's legs. This is a result of combining two separate strips of film to create the effect needed for the movie.
Continuity: When Jack lowers Ann down a rope off the cliff, Ann is wearing shoes during one shot when she has been continuously barefoot.
Continuity: Fifteen men chase Kong through the forest. At the end of the pursuit, only Driscoll and Denham are leftover. Nevertheless, when Denham speech to the audience, he tells "twelve of our party met horrible deaths". Then, one man inexplicably disappears.
Errors in geography: Skull Island is in the Pacific. During the ceremony of preparing the bride who will be sacrificed to Kong, you see Leopard skins as part of the decorations of the set. Leopards are exclusively African animals.
Revealing mistakes: When Kong descends from the scaffolding and rampages through the theatre, in one shot from the back he is roughly the same size as a normal gorilla
Revealing mistakes: Kong's fur seems to ripple as he moves, this is due to the indentations made in the fur of the Kong model by the fingers of the men who were constantly touching it to change its position slightly to produce the stop-motion animation effects.