A
- Aamon or Amon (Christian demonology)
- Abaddon/Apollyon (Christian demonology)
- Abalam (Christian demonology)
- Abezethibou (Testament of Solomon)
- Abraxas (Gnosticism)
- Abyzou (Jewish mythology)
- Adramelech (Assyrian mythology, Christian demonology)
- Aeshma (Zoroastrianism)
- Agaliarept (Jewish mythology)
- Agrat Bat Mahlat (Jewish demonology)
- Agares (Christian demonology)
- Agiel (Jewish mythology)
- Ahriman/Angra Mainyu (Zoroastrianism)
- Aim/Haborym (Christian demonology)
- Aka Manah/Akem Manah/Akoman/Akvan (Zoroastrianism)
- Ala (Slavic mythology)
- Alal (Chaldean mythology)
- Alastor (Christian demonology)
- Alloces/Allocer (Christian demonology)
- Allu (Akkadian mythology)
- Amaymon (Christian demonology)
- Amdusias (Christian demonology)
- Ammut (Egyptian mythology)
- Amon (Christian demonology)
- Amy (Christian demonology)
- Anamalech (Assyrian mythology)
- Andhaka (Hindu mythology)
- Andras (Christian demonology)
- Andrealphus (Christian demonology)
- Andromalius (Christian demonology)
- Antichrist (Christian demonology)
- Anzu (Sumerian mythology)
- Apep (a.k.a. Apophis) (Egyptian mythology)
- Armaros (Jewish demonology)
- Archon (Gnosticism)
- Asag (Sumerian demonology)
- Asakku (Babylonian mythology)
- Asb'el (Jewish mythology)
- Asmodai/Asmodeus (Jewish folklore and Christian mythology)
- Astaroth (Christian demonology)
- Asura (Hindu mythology)
- Azazel / Azaz'el (Jewish demonology)
- Azi Dahaka/Dahak (Zoroastrianism)
Read more about this topic: List Of Theological Demons