Other mistake: At the end of the intro, before the logo appears you can see Mojo Jojo's brain. His brain is green and it should be pink.
Monkey See, Doggie Do / Mommy Fearest - S1-E2
Plot hole: Why would the professor just get up and go to the store in the middle of the night, and come back expecting to find them in the living room?
Monkey See, Doggie Do / Mommy Fearest - S1-E2
Audio problem: In "Mommy Fearest", Ima Goodelady asks the Powerpuff Girls where they are going. Blossom tells her they're fighting crime, Buttercup speaks and then Bubbles adds, "Duh." However, her mouth doesn't move.
Buttercrush / Fuzzy Logic - S1-E4
Continuity mistake: When Buttercup punches a hole in the wall to see her sisters are being lowered into lava, the hole's initially quite small. In the next shot, the hole is noticeably bigger.
The Powerpuff Girls Best Rainy Day Adventure Ever / Just Desserts - S2-E10
Plot hole: The children decided that they hated the Powerpuff girls in one day. Then how did they have supervillain costumes and a van? The mom said they had lots of time to prepare.
The Powerpuff Girls Best Rainy Day Adventure Ever / Just Desserts - S2-E10
Plot hole: I don't think the police would throw the wife and children in the same jail cell as Harold.
The Powerpuff Girls Best Rainy Day Adventure Ever / Just Desserts - S2-E10
Continuity mistake: When Marianne calls Harold to the table, the plant in the middle disappears as they climb on top of it.
The Powerpuff Girls Best Rainy Day Adventure Ever / Just Desserts - S2-E10
Revealing mistake: When the van drives upstairs, you can see that it wasn't destroyed.
Speed Demon / Mojo Jonesin' - S2-E12
Revealing mistake: In the episode Speed Demon. When the girls are hugging each other outside the school, Blossom's eyelid on her left eye continues to vanish and pop back as she laughs.
Moral Decay / Meet The Beat Alls - S3-E13
Plot hole: Buttercup knocks out villains' teeth so she can get money from the tooth fairy. This makes no sense whether you believe in the tooth fairy, or not. If you do believe, the tooth fairy only gives you money for your own teeth, and I'm sure would be able to tell whether they're your own teeth or not. If you don't believe, and think it's the parents giving the kids money, then it's the professor who's giving Buttercup the money. You'd think he'd be suspicious about where Buttercup is getting all those teeth, and would question her accordingly.
Continuity mistake: When the girls first came out of the machine, they were actually just the size of insects, and the professor didn't need a helmet to see them, but when they was during the battle, he had to.
Makes Zen to Me/Say Uncle - S5-E16
Audio problem: In "Makes Zen to Me", Bubbles says "What's yours?" but her mouth doesn't match the words she spoke.
Answer: The Mayor says he could never get to the crime scene fast enough and Major Man says "of course not, you'd have to know about the crime in advance, like I do." Major Man let it slip he knew when the crimes were going to happen (because he was setting them up).
Bishop73