Continuity mistake: After Nedry has sprayed the shaving cream on his hands, (and after placing it on the pie) we see a sideview shot where he lowers his hands to his sides. The shot changes to the front and his hands are up again, drying his hands off with a napkin. It was too fast to move his hands.
Continuity mistake: When the five characters start to leave the helicopter upon arrival on the island, Richard Attenborough is not sitting opposite Jeff Goldblum as he was moments earlier as the helicopter descended to the pad.
Continuity mistake: When Grant nearly passes out after first seeing the Brachiosaurus, he sits down on the grass. In the following shot, he is shown kneeling.
Continuity mistake: In the scene from behind Dr. Grant we can see the cow being lifted straight up. You can see that the cow is rather close to Dr. Grant. Then the scene cuts and the cow is already in the middle of the top of the Velociraptor paddock. Judging from the distance between Dr. Grant and the paddock from the previous wide-shot, and the fact that Dr. Grant made no big moves, the crane couldn't pass that distance between the two shots. (00:27:35)
Continuity mistake: In the scene with Dr. Grant and Lex standing nose-to-nose with the T-Rex, the dinosaur sniffs at the humans, then turns its attention to pushing the Explorer around as Grant and Lex scramble for safety. When the T-Rex starts pushing the Explorer, a profile shot shows that the monster's foot is no more than two yards from the vehicle; yet, in the immediate next shot from the monster's point of view, the T-Rex is obviously positioned 10 or 15 yards away from the Explorer, much too far away to be pushing the vehicle.
Continuity mistake: After the first T-Rex attack, Tim's rover is still stuck in the tree, and Dr. Grant and Lex arrive at the base of the wall adjacent to a gushing storm drainage pipe. Dr. Grant assures Lex that he will return and goes to assist Tim. Whimpering, Lex clambers up to take shelter in the drainage pipe. However, there is now an inexplicable blue light glowing from deep inside the drainage pipe, illuminating Lex.
Continuity mistake: When the car first falls down the tree, you can see the adjustable headlight on the right tilts forward. In the next shot when the car hits the branch just before it hits Dr Grant, it does the same thing again. However in the next shot, the headlight is once again facing forwards. (01:17:10)
Continuity mistake: The T-rex completely destroys the outdoor bathroom facility that the lawyer ran into. The lawyer is perched atop the toilet and the remaining damaged wall behind him is tilted backwards. When the camera cuts to a shot where the lawyer is seen from behind and the T-rex is just about to eat him, the wall is missing. When it cuts back to a front shot, the wall is back again.
Continuity mistake: When Ian uses water to explain chaos theory to Ellie he drops the first water droplet on Ellie's hand and she immediately begins to tilt her head to the left to follow it. The very next shot shows Ellie's head has turned to the right. (00:47:40)
Continuity mistake: The two cars are stuck in front of the T-Rex enclosure and after the lawyer got out and ran away and left the kids in it, the driver's door is open, then shut in two other shots and then back to open.
Continuity mistake: When Tim is looking at the night goggles, Lexi says something to him. She continues to look at him for a second. Then in the next shot she suddenly has her back to him.