Revealing mistake: When Chief Brody sees the driftwood in the water, he sits down and takes his shoes off to wade in. As he sits down, his butt is already wet, even though he sits in dry sand.
Factual error: Brody would have also received a shock inside his raft due to proximity and water continuity.
Continuity mistake: In the beginning of the movie when Terry is water skiing, the boat has a 70hp 3 cylinder Johnson. When the shark is eating the boat it's a 1977 55 horsepower motor that still has the 70hp decal on it.
Other mistake: When the shark grabs and eats Marge, there is no blood at all.
Continuity mistake: When they are all sitting at breakfast, Michael says how he's going out sailing. The position of the mini Rice Crispies box on the table turns about 90 degrees between camera shots.
Continuity mistake: When Ellen Brody is talking with the Mayor and Hendricks on the docks, about her husband, her collar goes from under to over her jacket between shots.
Revealing mistake: When the shark attacks the sailboats with only Jackie and Sean aboard at the end, you can see that it is a totally different mechanical shark right down to the bad paint job.
Continuity mistake: When the two guys are trying to pull Mike back onto their boat, in the first shot they are pulling the front of his jacket. Then when the shot changes, they are pulling him up by the back of his jacket.
Continuity mistake: When Chief Brody is going into the water to get the large block of wood out, he leaves his shoes on the beach. But in the next shot when you see him about waist deep in water, his shoes are no-where to be seen on the shoreline where he left them.
