Codex Guelferbytanus or Codex Guelpherbytanus may refer to:
Codex Guelferbytanus A Codex Guelferbytanus B Codex Guelferbytanus 64 Weissenburgensis, which contains in the lower text of the palimpsests: Codex Guelferbytanus A, Codex Guelferbytanus B, and Codex Carolinus. Codex Vaticanus 354, formerly the Codex Guelpherbytanus Minuscule 126, also called Codex Guelpherbytanus (C) by Franz Anton Knittel Minuscule 429, also called Codex Guelpherbytanus (E) by Franz Anton Knittel before it was called Act. 69, Paul 74., and Apoc. 30 by Scrivener