Continuity mistake: When we first meet Ariel, she is grabbing a mast and resting on the far right side of it. When the angle changes she's on the far left.
Continuity mistake: When Ariel and Flounder visit scuttle to show him the fork, the anchor swaps from laying flat on the sand, to standing-up laying a rock, and finally hanging loose resting against nothing.
Continuity mistake: During the hurricane, Eric's ship is tossed violently around on the waves. But when Ariel is thrown back into the water and the ship is seen from below, it's barely moving at all.
Continuity mistake: When Ariel goes to the surface to show Scuttle the fork, he first sees her through the telescope (which is the wrong way round). When you see Ariel through the telescope, she appears to be surrounded by the sea but when Scuttle takes away the telescope she is close up and right next to the rock he is on. Surely the rock would have seen through the telescope underneath Ariel not ocean.
Continuity mistake: When Ariel is trying to escape from the shark in the sunken ruin, she dashes out of a porthole without her bag of treasures. Then as she swims away, the bag is suddenly in her hands again.
Revealing mistake: When Ariel turns into a human for good at the end, Eric kisses her and then they are shown at their wedding. The last shot of the movie is the same shot as this one.
Continuity mistake: When Ariel enters the area where Eric's statue is, the weeds on the upper left part of the entrance disappear in further shots.
Continuity mistake: After the shipwreck, Grimsby grabs Eric and walks him away, between a rocky wall in the beach. When the angle cuts, the rocky wall is gone and the whole area is wider.
Continuity mistake: After having dinner with Eric, Ariel watches in the balcony. From the wide angle, the size of the window panes is very tall, but from the close-up it's much smaller.
Continuity mistake: When Eric washes up on the beach, he is either laying on a very small and narrow beach, or in a vast wide area, depending on the shot. This keeps changing back and forth.
Continuity mistake: When Ariel and Flounder first come to Scuttle, he drops an anchor and falls below. When he does this, a few feathers fall out of him. But the feathers never land.
Audio problem: In the Diamond Edition Blu-ray, near the end of "Part of your world." The shot of Ariel descending and Flounder's reaction shot are reversed, making Ariel's mouth out of sync with the song.
Continuity mistake: During "Kiss the Girl", Ariel is wearing a large bow in her hair. It disappears at one point when the shot shows her and Eric's silhouettes on the water.
Other mistake: The outline of Flounder's body is constantly drawn over the top of his fins.
Continuity mistake: While Ariel is having a bath, her dress gets put into the wash, but when it gets hung up it changes into a shirt.
Continuity mistake: When Ariel sits at the dinner table, a glass in front appears/disappears between shots.
Continuity mistake: During dinner, when Ariel is about to grab the fork and use it as a comb, the napkin underneath disappears.
Audio problem: In the beginning, when Flounder and Ariel are exploring the sunken ship, the ceiling caves in on Flounder. He swims toward Ariel and yells her name but his mouth is closed.
Continuity mistake: When Ariel peeps in the boat, the end of the boat is a couple of meters to her right. However, after Eric sees the statue and walks towards the hole where she hides, the distance has increased to over 10 meters.
Chosen answer: They are all throughout the film but the biggest one is when Eric is steering the ship to stab or skewer Ursula.
Disney-Freak