Continuity mistake: When Grumpy jumps the chasm to chase Dr. Marshall, there's a large green bulbous plant that moves from the side Grumpy jumped from to the one he lands on. It wasn't there before.
Continuity mistake: When Rick pushes down his socks to the top of his boots to cross the lava, they are back up to his knees in the next shot.
Character mistake: In the scene where Rick Marshall is playing the Banjo, he says he has been "doing some thinking with just him and the old four string". His banjo has five strings and you can see the five strings when he lays the banjo down.
Continuity mistake: The fossil of the lighter shown at the beginning of the film does not match how the lighter is pushed by the T-Rex into the mud later on as the text is face up. Since the lighter was pushed INTO the mud - the resulting fossil would have been flat with the words reversed on it.
Revealing mistake: Throughout the movie closeups of Enik's eyes reflect the lights and set around him that aren't part of the movie. During the scene when he's talking to Dr. Marshall about how the crystal controls the sleestack, you can see the white ceiling of the soundstage and lights which instead should be the sky.
Continuity mistake: During the pool scene there is a faraway shot of the area showing the three moons in the sky. However during the rest of the scene, we see similar angles and shots of the sky and the moons are nowhere to be seen.
Continuity mistake: After Holly takes the photo of Will with the T-Rex approaching behind him, in the next shot the dinosaur is a lot further behind as you see them running away from it.
Continuity mistake: After Holly yells at the T-Rexm after eating Dr. Marshall, the camera shot first shows the T-Rex passing her as she is now past its legs by the tail. When the camera shot changes we now see the T-Rex's legs haven't passed her yet.
Continuity mistake: The sun keeps moving from the left side to the right side of the catapult as Will and Holly are preparing it for Dr. Marshall.
Continuity mistake: When Will is asking Chaka if he is a cop, the quantity of fruit on the right side of the tree to the left of Chaka's head changes between shots.
Continuity mistake: In the scene when Holly removes Chaka's hand from her chest after learning his name, up close it's his left hand and in the next shot she's removing his right hand.
Continuity mistake: When Rick is lying in the back seat of the convertible in the desert, the speaker hanging next to him goes from being flush against the door when viewed from the front shot, to being crooked when viewed from behind.
Other mistake: Due to the gait of the T-Rex, its head moves rather significantly when it walks as seen throughout the movie. However when it approaches Dr. Marshall with the laser in its teeth, the laser is steady and able to pinpoint a line up his head in a very steady manner which would not have been possible.
Visible crew/equipment: Near the end of the movie, when Enik is pleading for his release you can see human hands in the reflection of his eyes. It should be claw type hands of a Sleestak.
Continuity mistake: When the mosquito is sucking on Dr. Marshall's neck, it keeps changing positions from higher up on his shoulder to more towards the front between shots. This is clear by watching the legs of the bug going from in front of his shoulder to being over the strap even when his head isn't moving.
Visible crew/equipment: At the end scene, you can see a few crew members standing in the reflection of Enick's eyes and its not any of the actors as he is facing the wrong direction for it to be them.
Continuity mistake: When the team lands on the pile of bones, there is some sort of yellow stuff holding it together. The pile is also flush up against the sides of the cave. When the Vines grab them and its a far away show, the yellow stuff disappears and is now a loose pile of bones that's no longer flush against the cave sides.
Continuity mistake: When Rick first meets Enik, the Sleestack are shown peering in through the portal. However throughout that entire scene, we see various other angles and the portal is nowhere to be seen.
Continuity mistake: When the dinosaur was climbing the stairs of the Sleestak courtyard passing next to Holly Cantrell, we can see that its position goes about 3 meters back when the angle changes between shots.
Factual error: When Dr. Marshall and team launch the tank of nitrogen into the mouth of the dinosaur, there's absolutely no reason why the tank would explode as it was swallowed whole and didn't experience any sort of impact that could have punctured, ruptured or broken the valve off the tank.