Goofs

When Nesmith and DeMarco are in the engineering room aborting the self-destruct sequence, DeMarco's uniform goes from being zipped up before they press the blue button, to being unzipped immediately afterward. (The scene has been edited to remove a segment where DeMarco seduces one of Sarris' soldiers.)

When Tommy is taking the Protector out of the spacedock, he scrapes the hull along the side of the spacedock, but the port engine should be in the way.

When Tech Sergeant Chen is helping to roll the Beryllium sphere on the planet, he is shown holding a large brown paper bag with his teeth. A split second later, the bag is gone.

When Jason Nesmith is first abducted by the Thermians, his limousine initially shows no front license plate. However, the limousine has a California plate in a subsequent shot.

The first time Sarris enters disguised as Fred, his arms are at his sides and he reaches for his gun. The second time, his right arm is behind him holding the gun.

On the original 2000/2001 DVD cast and crew listing, Justin Long is mistakenly billed as Brandon Long (Brandon being his character). On the 2003 DVD, this is corrected.

When the crew approach the surface of the planet in order to land, a crescent moon is visible in the sky. However the crescent shows that the light is coming from ahead and to the left, whilst the shadows on the planet are from a sun which is over to the right.

On their arrival home, the heroes say they must enter the "Black Hole" to warp space. However, the term should have been "Wormhole", as a black hole would suck them up and kill them.

Sarris' original interest in the Protector is the Omega 13, but after he captures the ship, he plans to blow her up without taking the device, despite the fact that everything on the ship works. However, at this point Nesmith has explained that it was a television series and that the actors don't know what the Omega 13 does, so even though everything else on the ship works, Sarris no longer believes that the Omega 13 is real.

Although Kwan is supposed to be playing a character of Chinese ancestry, it is very obvious that he is not of Chinese descent. However, during the rock monster scene, he says that "Kwan" is not his real name. This is, in fact, a reference to non-Caucasian characters often being portrayed by Caucasian actors throughout much the history of Hollywood.

When Jason Nesmith is explaining to Mathesar that they are actors from a series, he says "There is no Captain Taggart." In a following line, he uses the correct title "Commander Taggart". While this is not consistent with previous and later dialog, it is not incorrect. An officer's rank is not exclusive of his duty title. The commander of a vessel with a crew may be appropriately addressed by his rank, or as "Captain", regardless of his actual rank or frequency of use of either.

Commander Taggart admits in the mess hall that, while the crew found the Omega 13 on the original series, they had no idea what it did when activated. Unless specifics of the Omega 13 were discussed on the original series, it is highly unlikely that the Thermians would have been able to replicate it on the Protector since it was such a foreign, mysterious object. However, Brandon and his crew, as well as others have, apparently, had extensive discussions of the device and its nature, indicating the device had been discussed in series episode(s) of Galaxy Quest, at least hinting to its nature. The Thermians would have seen the same episode(s), and with their advanced technology, may have developed theories similar to Brandon's. Nesmith not knowing what the Omega 13 does, does not exclude Commander Taggart from suspecting or having discussed what it may do during the series. Also, not knowing what a device does, does not exclude discussion of its composition, which would have been duplicated to exact detail by the Thermians.

When Gwen and Jason are evading the chompers, Brandon, not Jason is saying "Go!" every time they need to move, which is why Jason's mouth doesn't move or show any indication that he just said something.

When Tommy is first pulling the ship out of the station, he scrapes the front of the ship. The way the wings project out on each side of the ship, the left wing should have also scraped the sides of the launch tunnel too, but it comes out unscathed.

When Jason Nesmith tries to explain play-acting to Mathesar, Sarris leans his head back and the actor's teeth can be seen behind the Sarris mask.

When Quellek steps into the hallway and is subsequently shot an entry/exit wound appears in his left chest area, indicating he was shot either from in front or behind. However, when Quellek crumples to the ground there is nobody behind him.

When Jason Nesmith and Gwen DeMarco are standing at the start of the chompers, the audio track has Gwen saying "Screw that!" However, she is clearly saying "Fuck that!" but was dubbed for the PG rating from MPAA.

When Sarris opens an oxygen seal with the Thermians, Gwen DeMarco says "They're suffocating." Her lips aren't moving.

At the beginning of the movie, after Jason Nesmith enters the dressing room of the convention center, the audio track has Tommy Webber (Laredo) saying, "You are so full of it, man!" However, looking at the visual, he is clearly using another expletive instead of "it". This overdub was necessary in order to obtain a PG rating from the MPAA.

Two teenagers enter and leave the restroom. At some moments, even though their mouths are not moving, they are heard to be talking and laughing.

At the convention, when Guy Fleegman is about to introduce Jason Nesmith, the backing band's only guitar player can be heard playing a simple 8th note pattern. Yet this very musician can be seen in the frame to the far right side, doing nothing.

When Jason Nesmith is fighting the "Pig Lizard" on the rock planet, right before he jumps over the creature, a crew member's hand can be seen maneuvering the puppet.

(at around 1h 3 mins) There is a view into Sarris' mouth, and Robin Sachs' real teeth can be seen.

When the actors are returning to the shuttle with the sphere, in a long shot, tents are visible in the background.

As the command section of the Protector turns onto final approach toward the convention, the Los Angeles skyline in the background is reversed. The shot is taken from northwest of downtown, but is a mirror image of how the skyline actually appears from that vantage point.

The Thermians appear to unable to grasp the concept of lying, and yet they have access to a great deal of Earth series, most of which would involve characters, even good characters, lying at some points. Gilligan's Island (1964), a series that it is confirmed they have watched, often had characters lying to each other. As such they should have figured out what lying was before they came across Sarris.

Fred advises Nesmith that the Beryllium sphere is damaged after their first battle with Sarris. Nesmith then explains to Mathesar that they only know the sphere as made of "wire and plaster", as it was used on the set of the Galaxy Quest series. It is too convenient that when they need a replacement Beryllium sphere, they are found on a planet very distant from Earth, and they appear and function exactly as they were scripted and created for the series. The only explanation is that someone within the original series cast or crew is in fact, an extraterrestrial who possessed knowledge of such exotic alien technology.

When the crew first arrives on the Protector, Mathesar tells them he does not believe there is a man, woman or child on his planet that does not know who they are (implying their homeworld remains occupied). But he later tells them he and his fellow Thermians on the ship are "all that are left", therefore returning to their homeworld would be pointless.

During the Galaxy Quest convention at the movie's beginning, Tommy Webber is introduced as "Crack gunner, 'Laredo'...Tommy Webber!" However, it is demonstrated through this movie (and in clips of the original Galaxy Quest series) that Laredo is the ship's helmsman, not the gunner. The role of helmsman also fits with his character's catchphrase "Pedal to the metal, Commander!"

In the credits for "Galaxy Quest: The Journey Continues", the credits read "Jason Nesmith as Commander Peter Quincy Taggert", though it should be "Taggart".

On the flight down to the beryllium sphere planet, Guy is crying because they don't know his last name. His last named in not revealed at this point. Yet on the planet, Jason says to Guy, "Flegman, set up a perimeter."