Le Serpent Rouge puzzle is a puzzle found in the video game Gabriel Knight 3: Blood of the Sacred, Blood of the Damned. It is a puzzle which surrounds a document of the same name, where protagonist Grace Nakimura attempts decipher riddles found in 13 different passages of the document. The puzzle was created by Jane Jensen, who also designed the game, and was inspired by the real-world poem of the same name, although she modified parts of it to make it solvable for players. Jensen was inspired in part by the works of author David Wood as well as the book The Tomb of God. The new fully controllable 3D camera was also a factor that went into the puzzle's design.
The puzzle has received generally positive reception, with adventure game fans regarding it as one of the best puzzles ever made. Critics from Adventure Gamers identified it as a highlight of Gabriel Knight 3, while Just Adventure and Adventure Gamers considered it one of the best of all time, the latter offering particular praise to the execution of its "over-arching nature".