A lot of the scenes with the Beta Unit were shot after main filming was complete because the test audience liked the comic relief of the Beta Unit scenes and the director decided they added more originality to the "boy gets to go to outer space" story. This is why in many of the Beta Unit scenes Lance Guest is obviously wearing a wig - he had cut his hair by the time those scenes were shot.
According to screenwriter Jonathan Beutel, the idea for "The Last Starfighter" came about, because he wandered into a video arcade and saw a young boy playing a video game and also at that time, he read the book "The Once and Future King" by T.H White and it occurred to him, that what if a video game had been a sword in a stone and a boy had scored an incredible number in the video game, which sent out a ripple effect across the universe.
Although Wil Wheaton's speaking scenes were cut, he can be seen in two scenes - running around the trailer park early in the film (wearing a red football jersey), and in the final scene, where he is obscured, standing behind Louis (wearing a blue jacket, possibly over the red jersey).
Atari actually programmed games for its 5200 SuperSystem and 400/800 series home computers as a tie-in with this movie. The games never went past the prototype phase (though copies do survive). Also, the game was nothing like the arcade machine Alex played in the film - the technology did not exist at the time to produce real-time 3-D polygonal graphics on a home machine. Rumor also has it that Atari produced one prototype Last Starfighter arcade machine, but it since has been lost. An early Atari 2600 program was revamped into the game released as "Solaris".
Robert Preston and Dan O'Herlihy had never met before this movie. When they finally met on the set, O'Herlihy was already in Grig makeup with a full-head mask. O'Herlihy introduced himself and Preston jokingly replied that of course he recognized O'Herlihy because he had "one of those faces."
In 2009, it was announced that a long-awaited sequel (titled "Starfighter") was going into production. The film would take place 25 years after the original film with Norman Snow confirmed to return as Xur. Ultimately, the sequel was never made. It may have followed a grown-up Louis Rogan, who misses his brother and is brought to Rylos to become a Starfighter himself or it may have involved Alex and Maggie's Rylos-born son or daughter who sets out to settle a score with Xur when Alex is killed during a Ko-Dan attack.
The small box-shaped robot shown after Alex gets his uniform on Rylos is a Heathkit HERO 1 robot (HERO was an acronym for Heathkit Educational RObot). The kit (which required extensive assembly) sold for $1,500, while the fully assembled robot sold for $2,500.
As Alex leaves the Starfighter's briefing to chase after Centauri, just before he runs into Grig, an announcer with a folksy-sounding voice says: "Now, Starfighters, if you will reach underneath your seats, you will find a packet which contains..." in an apparent parody of the survival kit briefing given by Maj. Kong aboard the B-52 in the film "Dr. Strangelove."
There is precedent for the Starfighter to be in command of the GunStar, rather than the Navigator. During the Second World War, the Armée de l'Air (French Air Force) had the Bomb Aimer as the aircraft commander so he could be in a better position to direct the aircraft. The Last Starfighter follows this practice.
Released a few years after the alleged release of the mysterious arcade game 'Polybius' which allegedly caused epileptic seizures and nightmares among the children who played it. The existence of this game is never been proven but there are strong similarities between the plot of the movie and the Polybius conspiracy that is still alive on various online forums.