Continuity mistake: At the beginning of the film when the first skull is found, the black workman is holding a cigarette in his right hand when he tosses the skull to the foreman: The next shot cuts in and the foreman says "It may be worth money" the cigarette is now in the left hand of the black workman.
Continuity mistake: When Roney and Barbara get out of the taxi, the street is in shadow, but in the next shot the sun is up, as it lights up the buildings in the background:. (00:36:05)
Continuity mistake: Just after the discovery of the insects in the spaceship, Roney runs out to tell Barbara to call the institute. Notice in between shots Barbara is standing on her own, then in the next shot a bemused Captain Potter suddenly appears standing right next to her. (00:38:53)
Continuity mistake: When the police sergeant, Quatermass and Barbara exit the station entrance to look at he derelict houses, at the moment he says "these are the houses" Barbara is facing directly forwards with her feet together, in the next shot as she replies " they really are derelict" she has turned left towards Quatermass and is standing with her feet together:. (00:16:20)
Continuity mistake: When the police sergeant, Quatermass and Barbara exit the station entrance, there is sign on the left in white letters on a black background that says London Transport No Admittance that is leaning against the wall, in next shot the position of the notice has changed position and is more forward facing. (00:16:20)
Continuity mistake: As the journalist in the red coat is walking quickly down the platform to join the press conference, she is seen from behind passing a large man stepping down from the platform and onto the track. In the next shot (in front of her) in the large man has disappeared. There is no way that he could have could have been hidden out of shot because he would have been walking alongside her down the track at the same time. (00:03:20)