Avalon Code (アヴァロンコード, Avaron Kōdo) is an Action RPG developed by Matrix Software and published by Marvelous Entertainment for the Nintendo DS. It originally released in Japan on November 1, 2008, and in North America on March 10, 2009.

Originally, the game's Book of Prophecy was intended to be a virtual book that could be used by the player to write in on by use of the Nintendo DS touch screen. Producer and scenario writer Yoshifumi Hashimoto said "in the beginning of the planning stages I thought about the players actually writing into the book "become weaker", but realized that this would take too long from the time the user thinks about it to the time it'll actually change. I also wanted players from other countries to all play the game the same way, so I decided to go with moving codes (symbols) around".

Avalon Code's character designs were done by the Japanese illustrator HACCAN, while much of the scenery and promotional art is accredited to the Japanese artist group Kusanagi. The opening theme, "Deep Forest", was sung by Japanese pop musician Kana Yazumi.

The games soundtrack was composed by Minako Adachi.