Character mistake: Sarah is a trained expert with predatory animals. But when her jacket is covered with blood (and not just any blood, the blood of the infant T-rex), and they're in a forest surrounded with carnivorous dinosaurs, and she knows that they need to pass through Velociraptor territory, and she thinks that the T-rex might follow them, she doesn't think to take the jacket off. And the others, who also happen to be hunters who would surely know that the blood would attract predators, don't say anything about it.
Plot hole: Near the end of the movie, Peter Ludlow (the snivelling nephew of John Hammond who wants to create Jurassic Park in San Diego) is addressing company stockholders as they wait for the cargo ship to arrive. He says something to the effect of: "I'd like to thank you all for being intrepid enough to show up in the wee small hours of the morning." Those last six words, and the color of the sky make it seem like it is four or five in the morning at the latest. For that early, San Diego is a busy town. The buses are running, business men are out, video rental stores are open (and with plenty of customers), and generally a lot of people are out to run away from the T-Rex. I have to imagine that the mass of people running in terror (even though it is early in the morning) were put in as an homage to old monster movies. Same thing could be said for the Japanese business men. (01:38:10)
Visible crew/equipment: In the scene where Ian is speaking to Mr. Ludlow while the group is walking through the rain. If you watch in the background when Ian says the word "Long" something falls from the top of the screen. An extra even follows the item as it falls, you can see his head move. Hard to miss. (01:11:30)
Factual error: When the T-Rex grabs Eddie out of the car, as soon as it takes its foot off the hood the car shoots forward and both it and the trailers fall off the cliff. In reality this wouldn't happen, the trailers would have simply started sliding again slowly. It's also shown that the cars wheels start turning faster as the car picks up speed going forward. Eddie had the car in reverse, as soon as his foot came off the pedal it would have stalled meaning the wheels wouldn't have turned and instead it would have just been dragged like it was doing before he got back behind the wheel.
Factual error: When Eddie is pulled from the car, it zooms forward and goes over the cliff. In reality this wouldn't happen. Right up until his death, Eddie had the car floored in reverse. Once he took his foot off the pedal the engine would have stalled. If a car is in gear and the clutch isn't depressed then the wheels won't turn (especially on wet mud!) The trailer would have had to drag the car but the wheels are shown turning freely.
Factual error: There is no way that the SS Venture could plow into the dock as depicted. Easily pulling a 30-foot draft, the Venture would have grounded out a mile away from the shoreline, unless the ocean was 30 feet deep right off the beach.