Helheim (ヘルヘイム Heruheimu) could refer to:
- Helheim Forest - The forest that is the medium for the "Trial of Evolution"
- Femushinmu Planet - The planet that was given the codename Helheim by Yggdrasill Corporation where which the Helheim Forest was discovered.
- DJ Sagara - The sentience of the Helheim Forest who took on the name Helheim as a representative description of his being.
- Planet of Helheim - The newly-born planet where Kouta Kazuraba sent the Helheim Forest and the Inves after acquiring the powers of the Fruit of Knowledge.
- This dimension was directly named after the Underworld in Norse mythology.