Continuity mistake: In the fox hunt scene Hippolyta is initially shown riding a horse with her dress firmly tucked under her. The following shot of her has the dress flying partially up around her waist and exposing a fair amount of flesh. The subsequent shots again have her dress firmly tucked under her.
Continuity mistake: When Theseus decides Hermia's fate (at the beginning) Theseus picks up and closes the Law book laying on his desk and hands it to one of the court attendants. In the next shot of Theseus, the book is back open on the desk.