Edward Van Sloan's character, named "Van Helsing" in Dracula (1931), inexplicably has his name changed to "Von Helsing."
Dracula's Daughter (1936) opens showing the aftermath of the mayhem at Carfax Abbey, which happened in Dracula (1931). Although a 1930s audience, who had neither television nor home video, could never notice this, it is obvious to modern DVD enthusiasts that the positions of the bodies and furniture, scattered about, are grossly inconsistent between the two movies.
Countess Zaleska, a vampire, handles a crucifix without harm. Her father, Count Dracula, also a vampire, could not even come near a crucifix in the previous Universal Dracula film.
At the conclusion of "Dracula", Van Helsing drives a thin piece of wood into Dracula's heart. In this film, the policeman sees the corpse with a much heavier tent peg protruding. Also in the original, Renfield drops off the side of the staircase after being strangled. Here he is at the bottom of the staircase, which has floor to ceiling walls on both sides.
At Lady Esme Hammond's party, Sir Aubrey is seen standing between Countess Zeleska on the left, and Dr. Jeffrey Garth on the right. But when Jeffrey begins speaking to the Countess directly, in both long and close shots it is clear that he has changed positions with Sir Aubrey. Jeffrey is now in the center and Sir Aubrey on the right, without them having been shown to have made the switch.
Just before the sergeant leaves his constable alone in the station (just before Zaleska makes her first appearance), he hands him a pistol. Even in 1936, it is extremely unlikely that a non-metropolitan UK police officer would have access to or authority to issue firearms without exceptional circumstances (which would not have included guarding two corpses).
An ambulance seen arriving at a hospital is an American square back hearse type and by freeze framing is seen to be left hand drive so completely out of place.
After Van Helsing is arrested in Whitby he's sent to Scotland Yard but the local police would deal with the case first and then send him to the County Police. Scotland Yard would never come into it.
Three actors' names are misspelled in the credits: Halliwell Hobbes (as Hobbs), Nan Grey (as Gray), and Claud Allister (as Claude).
Garth tells the cabby he will pay him 5 pounds for the trip to Dracula's castle, but it appears that he says 25 pounds (the "20" was muted).
When Lili is eating a sandwich, her speech is perfectly clear, even though her mouth is supposedly full of food.
Although the film takes place mostly in London, telephones consistently ring one ring at a time, whereas British phones have always used a double ring.
In both Dracula (1931) and Dracula's Daughter (1936), Whitby is constantly alluded to as being right next to London. In fact, they are 200 miles apart. Apparently screenwriter Garrett Fort misread the passages that Bram Stoker wrote in the novel's chapters set in Whitby.
When the police came upon the mayhem at Carfax Abbey (caused in Dracula (1931)) in the first scene, where were the primary witnesses, Mr. and Mrs. Harker? Their names would certainly have come up at some point while Dr. Von/Van Helsing was being booked and the crime scene was being examined. Furthermore, their suspicious departure from the scene should cause them to be regarded as fugitives and suspects. Yet they are never mentioned in this movie.
Whatever mysterious force is causing the earth to shift in the police cell at Whitby (when Dracula's body is in storage there) is left completely unexplained, and apparently serves no purpose in the plot other than to give the policemen a quick scare.
Missing from the first film are Dr Seward, Johnathon Harker, and Mina. Harker's bride to be. They could easily corroborate Van (or Von) Helsing's story.
The sergeant refers to the police station to which the body of Dracula has been brought as "Whitby Jail". The term "jail" is only used in the UK to refer to dedicated prison facilities (and mostly in a historical context: e.g. Newgate Gaol). It is not used to refer to police stations.
Van Helsing addresses one of the police officers as "constable", in spite of his obvious sergeant stripes. Although this may be Van Helsing's error, it is curious that the officer (who is established as a pompous, self-important character) does not attempt to correct him.
Prof. Van Helsing claims that Count Dracula had been dead for about 500 years, and that his daughter Countess Zaleska died about 100 years previous to the date of the film. If Van Helsing is assuming that, 400 years after his death, Dracula would have been unable to sire a child, then he could be wrong about at least one of the dates of death. However, there is no proof that a vampire cannot accomplish such a feat.