The Werewolf Principle is a 1967 science fiction novel by American writer Clifford D. Simak.

A British hardcover was also released in 1967, with translations following into French, Italian, German, Portuguese, Dutch, and Lithuanian.

[1] The novel deals with an amnesiac space traveler who discovers he shares his body with a wolf-like alien and a cybernetic consciousness.

[2] Judith Merril gave The Werewolf Principle a mixed review, saying that "it was an ambitious concept, obviously thought through seriously and with care; it deserved something more than to turn into a (very) well told routine novel.

[4] Analog reviewer P. Schuyler Miller rated the novel "good, but not outstanding", praising Simak's depiction of "a totally strange, but strangely satisfying, future Earth" while uncomfortable with the story's "pretty violent action".