Iusaset (/juːˈsæsɛt/; "the great one who comes forth") or Iusaas (/aɪˈjuːsəs/) is the name of a primal goddess in Ancient Egyptian religion. She also is described as "the grandmother of all of the deities". This allusion is without any reference to a grandfather, so there might have been a very early, but now lost, myth with parthenogenesis as the means of the birth of the deities from the region where her cult arose near the delta of the Nile. Many alternative spellings of her name include Iusaaset, Juesaes, Ausaas, and Jusas, as well as in Greek Saosis /ˌseɪˈoʊsᵻs/.
In Ancient Egyptian art, Iusaaset appears as a woman wearing the horned vulture crown with the uraeus and the solar disk in it, and she carries an ankh in one hand and a scepter in the other. The Egyptian vulture, most sacred to the ancient Egyptians and symbolizing Nekhbet, one of the Two Ladies protecting Egypt, was thought to reproduce though parthenogenesis also. This association might be the basis for the similar view about the motherhood of Iusaaset. The vultures also were considered extremely good mothers. The horns, the uraeus, and the solar disk make a religious connection to Bat and Hathor.