Continuity mistake: In Pikachu's Vacation, when Pikachu and the rest of his friends are pulling Charizard's head out, the rope that they use was not there during the previous shots.
Continuity mistake: When Ash & co. are in the boat with Team Rocket (who's dressed as Vikings), watch Brock's shirt sleeve (The one away from Misty) when Misty puts Togepi inside her knapsack. It goes from a dark orange to green (the same color as Brock's vest) for a few frames before turning back. (00:33:26)
Continuity mistake: When Brock looks at the picture of Nurse Joy, in the closeup of the picture Brock casts a shadow on it, but in the previous shot he didn't.
Continuity mistake: When Fergus goes to Gyarados after Mewtwo reflects its Hyper Beam, you can see the back of a Nidoking, but Fergus has a Nidoqueen. (00:43:23)
Continuity mistake: When Mewtwo begins to make the storm, his hand is pink. But in the later shot while he's making the storm, it's greyish purple again.
Continuity mistake: When Officer Jenny speaks after Fergus puts his right foot forward, the clothes and accessories of some people change. (00:31:08)
Continuity mistake: When Ash says, "Wow!" the bowl of fruit changes as well as a cup changing from being on right of it to the left of it. (00:40:25)
Continuity mistake: In Ash and his friends' first appearance, the cream and orange stripes on Ash's bag turn green. (00:21:08)
Continuity mistake: When Misty retrieves the white card, the marks on Ash's cheeks go from present to absent. (00:27:35)
Continuity mistake: When first showing a closeup of Ash, a plate next to the centre of the table goes from present to absent. (00:21:19)
Continuity mistake: When Mewtwo says that they stood as equals, Giovanni's right hand is five centimetres away from the nearest pole to the left of him, but in the next shot, it is one centimetre away. (00:08:20)
Suggested correction: As explained in the DVD commentary, Team Rocket don't know everything about Pokemon. They thought it was an Alakazam though.