- When they're on the island and the InGen helicopters are flying in, Ian Malcom takes the binoculars and looks through the wrong end.
- When the vehicle is hanging off the cliff and the glass at the rear slowly begins to crack, it does so like sheet ice (or conventional window glass). Safety glass in vehicles would either be laminated (in which case it wouldn't shatter at all), or it would break into a million fragments.
- When Sarah and Nick return to the trailer with the baby T-rex, there is a shot of Nick carrying the rex towards the operating table. Look between the baby rex's legs - there are a series of wires leading from a opening in the animatronic dinosaurs belly to a bulky device (presumably a battery pack) in the actor's pocket. Once you know where to look for the wires, you will notice them in many other shots in the film when various actors are holding the baby rex.
- When the Tyrannosaurs have destroyed the car during the minutes before the trailer sequence, you can see that the destroyed car is nowhere when Eddie Carr tries to save Malcolm.
- When the Tyrannosaurus Rex is being delivered to the San Diego Harbor Dock, there is a numerous-shot sequence that there are several human hands attached to many parts of the S.S.Venture. However, even if the Tyrannosaurus Rex got free, then the hand in the area would have to have the area containing the remains of a employee destroyed. This is left out because Velociraptors were supposed to do the damage, but the scene was deleted. Or unless that Pterosaurs or a possible sea reptile had done the damage.
- When the Triceratops is attacking the InGen Site Base Camp, it's tail is invisible when we see more dinosaurs released.
- When Sarah and Kelly are trying to escape the shed by digging a hole, a Velociraptor pops out. However, when the raptor is fully in the shed, the ground is flat again and the hole isn't there.
- When Roland Tembo is arguing with Peter Ludlow that they are trying to set base camp on a game trail, Peter Ludlow is next to him, but no one is driving the vehicle. How can there be no driver? And also, how did Peter Ludlow quickly get to the back of the car without getting out when he was inside? Perhaps there's a way into the back from where he was sitting, it is a very advanced car, as we see in the movie/
- The InGen employees under the control of Roland Tembo and Peter Ludlow are running from the Tyrannosaurus Rex, about only 10 are visible. However, when they run into the long grass while the Velociraptors attack them, none of the other men who were fleeing the Tyrannosaurus was seen being eaten by Velociraptors. And Ajay Sidhu is not seen running from the T-Rex when he has popped out warning them not to go into the long grass. The groups split up during their flee from the T-Rex.
- When Hammond is explaining Isla Sorna to Malcolm, we see the director's blue jeans reflected on the mirror of Hammond's desk when it goes from left to right when Hammond is in his bed.
- When the rope unties from the tree Eddie Carr ties to, the three protagonists Malcolm, Sarah, and Nick Van Owen are seen falling, but they are visibly seen with crew-wires attached around their waists.
- Towards the ending, the Tyrannosaurus Rex is seen attacking San Diego, but some errors are made. When a woman in a red sedan is screaming while backing up her car, there are two actresses who are seen. Also, when the T-Rex attacks the bus, the bus is full of people, but the dinosaur crashes it's head into the bus, and only a few people are seen crashing out of the bus, and we don't see those people on the floor again. Also, how does the bus crash into a video store if it was driving perfectly on an angle in the street?
- The dinosaur Pachycehpalasaurus is much more bigger than the ones portrayed in the film.
- The Stegosaurus portrayed in the film are almost twice as large as the real animal in the world.