Continuity: In the first scene featuring nextdoor neighbor Mrs. Bates, she places the telephone on the coffee table twice.
Continuity: When Jane is shocked by her reflection in the mirror, the expression in her face as well as her posture has changed in the next shot.
Plot holes: When Edwin calls Jane to arrange an interview, she tells him to come to her house - but never provides an address.
Continuity: Mrs. Bates pays her first visit to the Hudson home during early morning hours (Jane is fixing breakfast) but when she returns to her own home next door supposedly just minutes later, outdoor shadows indicate that hours have passed and it's now early-mid afternoon.
Continuity: In the film's final scene, when Baby Jane walks up to the ice cream vendor, her lipstick is much lighter than in the rest of the film. Moments after, her lips are once again covered with darker lipstick. Additionally, during the dancing scene subsequently on the beach, even though it's obviously hot out, the ice cream shows no signs of melting whatsoever.
Continuity: When Blanche removes the note she has typed to throw to her neighbour from the typewriter, the machine's carriage is at the far right. The next shot is a close up of Blanche adding a handwritten footnote to the letter -- the typewriter carriage is now positioned centrally.
Continuity: In one scene Jane parks the Lincoln convertible in the garage head-in. The next time we see the car, it's been backed into the garage.
Miscellaneous: 40 seconds into the film, there's a close up of a poster proclaiming "THE ONE AND ONLY!! BABY JANE HUDSON: THE DIMINUTIVE DANGING DUSE FROM DULUTH" (instead of "Dancing Duse").