Seth was the third son of Adam and Eve in the Bible.
Seth may also refer to:
- Strong exponential time hypothesis
- Seth (given name)
- Seth (surname)
- Seth (cartoonist)
- Seth, Germany
- Seth Material, a collection of writings allegedly from "Seth" a disembodied entity channeled by Jane Roberts
- Set (deity), also known as Seth
- Seth (band), a French Black metal band; see Originators of the Northern Darkness – A Tribute to Mayhem
- Cyclone Seth (2021), a weak tropical cyclone that made landfall on Australia