Lists of legendary creatures
- Yacumama (South America) – Sea monster
- Yacuruna (Indigenous people of the Amazon) – Mythical water people, with backwards heads and feet
- Yadōkai (Japanese) – Malevolent, nocturnal spirit
- Yagyō-san (Japanese) – Demon who rides through the night on a headless horse
- Yaksha (Buddhist, Hindu, and Jainism) – Male nature spirit
- Yakshi (Keralite) – Vampire
- Yakshini (Buddhist, Hindu, and Jainism) – Female nature spirit
- Yakubyō-gami (Japanese) – Disease and misfortune spirit
- Yale (Medieval Bestiaries) – Antelope- or goat-like animal with swiveling horns
- Yali (Hinduism) – Lion like creature often symbolic for protecting temples
- Yallery-Brown (English) – Nature spirit
- Yama (China, Korea, Japan, Buddhism, including Tibet) – Wrathful god
- Yama-biko (Japanese) – Echo spirit
- Yama-bito (Japanese) – Savage, mountain-dwelling humanoid
- Yama-chichi (Japanese) – Monkey-like mountain spirit
- Yama-inu (Japanese) – Dog-like mountain spirit
- Yama-otoko (Japanese) – Mountain giant
- Yamata no Orochi (Japanese) – Gigantic, eight-headed serpent
- Yama-uba (Japanese) – Malevolent, mountain-dwelling hag
- Yama-waro (Japanese) – Hairy, one-eyed spirit
- Yanari (Japanese) – Spirit which causes strange noises
- Yaoguai (Chinese) – Animalistic demon or fallen gods
- Yara-ma-yha-who (Australian Aboriginal) – Diminutive, sucker-fingered vampire
- Yatagarasu (Japanese) – Three-legged crow of Amaterasu
- Yato-no-kami (Japanese) – Serpent spirits
- Yeth hound (English) – Headless dog
- Yeti (Himalayan) – Mountain bigfoot
- Yilbegän (Turkic) – Either a dragon or a giant
- Yobuko (Japanese) – Mountain dwelling spirit
- Yōkai (Japanese) – Supernatural monster
- Yomotsu-shikome (Japanese) – Underworld hag
- Yong – Korean dragon
- Yōsei (Japanese) – Fairy
- Yosuzume (Japanese) – Mysterious bird that sings at night, sometimes indicating that the okuri-inu is near
- You Hun Ye Gui (Chinese) – Wandering ghost
- Yowie (Australian Aboriginal) – Nocturnal human-ape hybrid, also Yahoo
- Ypotryll (Heraldic) – Boar-camel-ox-serpent hybrid
- Yuan Gui (Chinese) – Distressed ghost
- Yukinko (Japanese) – Childlike snow spirit
- Yuki-onna (Japanese) – Female snow spirit
- Yūrei (Japanese) – Ghost
- Yuxa (Tatar) – 100-year-old snake that transforms into a beautiful human