The Book Series is here

Explore →

Siyokoy: The Siyokoy is an aquatic humanoid creature from Philippine mythology, noted for its fish-like features such as scales, webbed limbs, and fins.

Siyokoy - The Siyokoy serves as a cautionary figure, embodying the dangers hidden in Philippine waters and reflecting the complex interplay of indigenous beliefs and historical influences.

Siyokoy

Siyokoy - The Siyokoy serves as a cautionary figure, embodying the dangers hidden in Philippine waters and reflecting the complex interplay of indigenous beliefs and historical influences.

Quick Story →

the legend in five swipes.

The Siyokoy is an aquatic humanoid creature from Philippine mythology, noted for its fish-like features such as scales, webbed limbs, and fins. It is renowned for its hostile nature toward humans, often attacking by drowning them. The creature’s blend of indigenous and Chinese-influenced attributes underscores its unique place in Southeast Asian folklore.

How did the legend of the Siyokoy begin?

Siyokoy: The Written Sources

What did people say the Siyokoy looked like?

How did location shape the story of the Siyokoy?

Siyokoy: Cross-Cultural Comparisons

How did the Siyokoy survive into the modern world?

Interesting Fact

Unlike many mermaid legends that portray their subjects as enchanting and benign, the Siyokoy is distinctly malevolent, serving as a potent emblem of the dangers lurking beneath the surface of Philippine waters.

Enjoying this creature? A quick share helps us keep expanding Mythological Creatures. If not, no worries, enjoy the collection.

Mythological Treasures

Loading...

Japanese Yōkai: A field guide to the spirits and demons of Japanese folklore

Fifteen spirits, with the signs to watch for and what the old tales say to do if you meet one.

Loading...

Greek Myths: A field guide to the monsters of ancient Greece

Every monster here earned its place in legend, and each gets a full page of artwork and the story behind it.

Loading...

Norse Sagas: A field guide to the beasts of the Viking world

Drawn from the saga accounts themselves, with the powers, weaknesses and doom of each being set out.

Curated sponsor space

One subtle banner. Thousands of myth lovers.

We offer a small number of curated sponsor spots for relevant books, courses, games, and art. No clutter, just well-matched partners.

Partner with us

Quick Creature Info

Associations:

Element: Water

Our Mythic Legendary Rating:

Mythic Ember
Mythic Ember rating

Also Sometimes Known As:

SyokoySiokoy

Habitat:

water bodiesWaterPhilippinesOften found in both freshwater and marine environments throughout the Philippine archipelago.Aquatic environments (rivers, lakes, oceans)Philippine waters

Supernatural Powers:

Capable of drowning victimsAggressive and predatory nature

Physical Attributes:

scaleswebbed limbsfinsaquatic adaptationsnatural fish scaleswebbed extremities

Abilities:

Enhanced aquatic locomotionPowerful swimming via webbed limbs and tail finNatural armour provided by scalesAdaptation to aquatic environment

Behavior:

HostileAggressive towards humans; known to attack and drown those who venture near its watery domain

Lore:

Aquatic predator and malevolent water spiritPhilippine mythologyThe Siyokoy serves as a cautionary figure, embodying the dangers hidden in Philippine waters and reflecting the complex interplay of indigenous beliefs and historical influences

Related Creatures, Tales or Lore

References

Discover Another Mythical Legend You May Not Have Heard Of?

Uncover the mysteries of ancient folklore and expand your knowledge of legendary beings from cultures around the world.

Dare to Meet the Lysianassa....

The Mythological Creatures Book Series

Yōkai, Greek, Norse, Egyptian & Chinese. Five illustrated field guides to the creatures the old stories either warned or told you about.

Mythological Creatures Field Guide: Japanese Yokai book coverMythological Creatures Field Guide: Greek Myths book coverMythological Creatures Field Guide: Norse Sagas book cover
Mythological Creatures Field Guide: Egyptian Legends book coverMythological Creatures Field Guide: Chinese Beasts book cover
Explore the books

Curated by the Mythological Creatures Team

Series editor: Mythological Creatures Directory

Primary desk: Asian & Pacific Myth Cycles Desk

(rev. November 2025)