When Humbert comes through Quilty's door in the beginning, he walks by a painting in the hall. Some moments later he is shooting through the same painting on the staircase. When Quilty is first shot in the leg, a covered chair is visible at the top of the stairs, and it isn't until Humbert reloads that the painting that he hides behind before being shot is seen.
In the filling station where Humbert is looking out the window, the car he sees is a white 1956 Chevrolet, but the car following him in the next few scenes is a dark-colored 1957 Chevrolet.
When Humbert starts his journey to pick up Lolita, the white station wagon at the Camp Climax sign has a license place that reads 2178 and seems to be from a different state than the other plates. The car Humbert parks at the service station has a lamp attached to the front grille and carries number plate 17459. A few minutes later, when Humbert has the blow-out (which seems to leave all four tires intact), the lamp is missing and the car has a white number plate that reads AC629. The car that has been trailing them also has this same type of license plate. It is visible on the front of the car and on the back, when it turns around. At the end of the film, the car has the 17459 license plate again.
When Humbert and Charlotte discuss sending Lolita to the girls camp, Charlotte holds a lit cigarette in a cigarette holder in her left hand in the shots facing Humbert. When the shots face Charlotte, there is no cigarette in either hand and no smoke. This changes back and forth as the shots change between the two characters.
A bottle seen standing on the piano bench in Quilty's house is no longer there when Quilty sits to play at the piano.
Punctuation error in the opening credits: a line reads, "Miss Winter's costumes by Gene Coffin". It should be "Miss Winters' costumes by Gene Coffin".
It may be thought that there is an incorrectly used apostrophe on the sign outside the high school play that reads "Beardsley High Thesp's" (i.e., an apostrophe is not used for a plural construction). However, an apostrophe also is used to indicate the omission of letters within a word (as with contractions). In this case, the apostrophe is "standing in" for the letters "ian".
Director Stanley Kubrick walks out of the very first interior shot (center to right bottom) of Humbert entering Quilty's house.
There is a moving shadow of a crew member on Humbert's back when he is talking to Lolita in the kitchen of her house; the same movements can be seen in a crew member's reflection on the television screen facing the camera.
Charlotte Haze's house is obviously British in architectural style as is the street in front of her home, although the location for her house is New Hampshire, USA according to the voice over in the film. Much of the film was shot in the UK.
As Humbert and Lolita are leaving Beardsley, they drive through an intersection with a traffic light visible for the intersecting traffic. The light changes from red to green just prior to the car entering the intersection, meaning that they go through the intersection against the light.