Legion(s) of Hell or Hell's legion(s) may refer to:

• Legion (demons), a group of demons in Christianity
• The Legion of Hell, an army of llaneros who fought against the Second Republic of Venezuela led by Simón Bolívar

• Legions of Hell, the inhabitants of the fictional location Hell in works published by DC Comics
• Legions of Hell, a 1987 fantasy novel by C. J. Cherryh in the Heroes in Hell series
• Legions of Hell, a style of play in the pen and paper role-playing game Noctum
• Legions of Hell, a group of antagonists in the 2022 superhero film, Black Adam
  • "Legions of Hell", an eponymous track on the score album Black Adam

• Devil (Dungeons & Dragons)
• List of demons in the Ars Goetia