There is an extra "two months later" scene at the very end, after all the end credits.

After Uncle Rico throws the steak at Napoleon when he's riding his bike, Rico sits back down on the porch and you can see him discreetly spit something into his hand and put it down. According to the DVD commentary, this was the bite of steak he was eating, because Jon Gries, who played Uncle Rico, didn't eat red meat. Between shots he spat out all the many bites of steak his character had to eat.

The name "Napoleon Dynamite" is a pseudonym used by singer Elvis Costello for his 1986 album, "Blood and Chocolate." Although there is a resemblance, it is coincidence because it was unknown until it was already in production.

During the filming of the LaFawnDuh/Kip wedding scene the horse that Jon Heder (Napoleon) was riding galloped past the spot that it was supposed to stop on and went dangerously close to the camera crew. Jon franticly started giving the "stop" signal to the horse, who stopped so abruptly Jon was catapulted over the front of the horse and onto the grass in front of it. This fact is confirmed on the DVD featurette "The Perfect Wedding".

When Napoleon is in the locker room for P.E., he's sitting between the characters Randy (played by Bracken Johnson) and Lance (played by Brian Peterson). Randy's shirt says "Bracken" and Lance's shirt says "Peterson". They're not using the characters' names.

All of the students in Napoleon's school are credited at the end of the movie. Over 150 names.

Jon Heder made short videos with his roommates in college, closely related to Napoleon Dynamite.

All the main actors, except Jon Gries, are Mormon, which is why they don't swear during the movie.

Because Napoleon Dynamite was such a giant hit among young people, especially college students, the actors were asked to make appearances at different college graduations. At one, Jon Heder, who portrayed Napoleon was asked by a student to throw a steak at his face. He agreed, hit him square on, and then autographed the steak.