Continuity mistake: When the evil spell takes over the tree in the Forest of Feelings, Brave Heart Lion has his symbol on his belly in the shot as Swift Heart rabbit is coming to the rescue. They don't get their symbols until the end of the movie. (00:41:05)
Continuity mistake: When Taran, Princess Elonwy and Fflewddur try to escape from the Horned King's castle, Taran opened the gate by removing the chains. The next shot the gate is closed and chained, the last shot the gate is open again, and the boat is pushed trough by Taran. (01:06:33)