Code Lyoko's graphic bible originated from a student graduation short film by Thomas Romain and Tania Palumbo, two students at the Gobelins school, screened at the 2000 Annecy International Animation Film Festival as part of 'Les enfants font leur cinéma'.

That original short film was a clear homage to Japanese animator and director Kōji Morimoto, known for works like Memories and Animatrix - Beyond.

The project was first developed as a 2001 pilot for Antefilms called 'Garage Kids,' created by Thomas Romain and Tania Palumbo, before evolving into Code Lyoko.

Thomas Romain, the project's original instigator, left the production in 2003 due to deep disagreements with producers over artistic and narrative choices, and refocused on his other project, Ōban Star-Racers.

In the Garage Kids pilot, the virtual world's design was much more complex and unusable for a regular series, Aelita did not exist yet, and the three boys shared the same dorm room; Odd was also shown joining the group after they were already fighting XANA, unlike in the final series.

As a tribute to the abandoned Garage Kids project, season 4 of Code Lyoko names a location in the virtual world 'Garage Skid'.

The factory setting was inspired by the former Renault factory in Boulogne-Billancourt, located on an island similar to Île Seguin, while Kadic Academy was modeled after Lycée Lakanal in Sceaux, sharing an identical layout.

The students' school is named Kadic as a nod to science-fiction author Philip K. Dick, who inspired the series, and the writers based the supercomputer concept on the real-life Cray X-MP.

The writers have acknowledged that the concept of virtualization into a digital world was inspired by the films The Matrix and Tron.

In the French dub, several actors voiced multiple characters, such as Raphaëlle Bruneau performing both Jeremy Belpois and Odd Della Robbia, and Frédéric Meaux voicing Jim Morales, Takeo Ishiyama, Michel Belpois, Mr. Della Robbia, James Dunbar, and even the dog Kiwi.

Code Lyoko: Evolution, the live-action/CGI hybrid follow-up series, was filmed from June to September 2012 in Angoulême, using locations including the Lycée Guez-de-Balzac and Aredi studio.

Code Lyoko received the French Export Prize (Prix Français de l'Export) for animation in December 2006 and was ranked as the third best-performing show on Cartoon Network in the US that same year.

The fictional band Les Subdigitals, part of the Code Lyoko universe, released two real albums with identical music in 2006 and 2007, differing only in that the lyrics were in French for the first and English for the second.

A tetralogy of Code Lyoko novels was published in Italy under the pen name 'Jeremie Belpois,' written from that character's point of view; none of these novels were ever translated into English, and the French publication of volumes 3 and 4 was cancelled due to poor sales of the first two.