If you posit that zombies are created by magic, it's fantasy. If you posit that zombies are created by disease processes, radiation, scientific intervention, alien possession, etc., it's science fiction.

Is Walking Dead Sci Fi?

Scary Series

The Walking Dead TV series. (Image credit: TWD Productions LLC.) Science-fiction television often explores profound themes of existence through the prisms of science, technology and the otherworldly.

Are zombies supernatural?

Zombies are Class 1 (Supernatural) entities, but unlike ghouls and mummies, zombies exhibit no supernatural behaviour or abilities beyond the mechanism that re-animates and preserves their bodies and minds.