Ao Yai Ai (Yai Ai Bay)

Diving Type shore dive , night dive
Level All levels
Depth 1 - 5 meters
Current none - strong
Water Temp 25.5 - 31.5 oC
Season June - September (However, weather conditions may change from day to day. Please check the weather conditions and avoid rainy and windy days.)
Highlight This place is considered a paradise for sea slug lovers, which are outstanding both in number and diversity. According to the database of  Sea Slug Thailand Group, there are at least 127 species of sea slugs reported here. One of them is a new genus recorded in Thailand called Hancockia sp.

Aow Yai Ai is not only home to various species of sea slugs, but also other creatures such as giant clams, coral shrimps, octopuses, butterflyfish, pufferfish, stonefish, seahorses, batfish, etc.

General Info

This small, quiet bay is a must for sea slugs lovers and considered one of the best shore dive sites in Thailand, both day dive and night dive. Maximum depth is approximately 5 meters.

It is a private bay but accessible to the public with restrooms, restaurants, and hotels available.

In the middle of the bay, there are a few small rocks called ‘Barbershop Rock’ (Hin Ran Tud Phom). Diving around these rock walls you will see many sea slugs species. Between the beach and the Barbershop Rock, there are hard corals interspersed with rocks that are covered in algae, sponges, and hydroids, which are food of sea slugs. The sandy area in the muck is also a good place for finding them as well.

At the left side of the bay (facing out to the sea) along the hill, there are coral reefs and areas of another type of algae, where other groups of sea slugs can be found. The right part of the bay is sand alternating with rocky areas.

Apart from diving activity, there is a beautiful cave on the nearby hill, Yai Ai Cave, which has beautiful stalagmites and stalactites. Nearby there is a viewpoint that can see the surrounding bay.


In some seasons there may be quite a lot of sea lice. Full rashguard is recommended. Anyone with allergies, please prepare your medicine.

Go There

  • Private car: map
  • Plane: Land at Chumphon Airport and rent a car to drive to the beach.
  • Train: Get off at Khlong Wang Chang Station (11.7 kilometers away) or Pathiu Station (14.2 kilometers away).
  • Bus

For air tank rental, there are service providers as follows:

  • The ocean dive center (097-953-9808)
  • Ms. Viana (Thung Wua Laen Beach) (089-645-5576)
 Chumphon - Koh Tao

How to Go toChumphon - Koh Tao


Nearest hospital

Pathiu Hospital (13 kilometers or 17-20 minutes away from Ao Yai Ai) Tel. 077591028