The Ultimate Guide

KochiDiving Guide

Kochi is one of the four prefectures of Shikoku, the smallest of Japan’s five main islands. All four prefectures border the ocean, but Kochi, facing the Pacific Ocean, is famous for scuba diving. This is thanks to the Kuroshio Current, one of the biggest and strongest ocean currents in the world, flowing from north of the Philippines. This current helps table,staghorn, and leaf corals to thrive. Many different species of tropical fish also make the waters around Kochi their home. From macro creatures such as pygmy seahorses to schools of pelagic fish such as greater amberjack, Japanese amberjack, and skipjack tuna, Kochi’s rich marine biodiversity attracts divers from all over Japan.

What you can see

Banded houndsharks in Ito.
Whitespotted bambooshark in Kannoura.
A red stingray hovers above the camera in Ito.
Jawfish are one popular creature.
Beard grunts can be found in Ito and Nishikawana.
Pigmy seahorses can be elusive, making it a real delight when you finally find one.
Beautiful nudibranchs everywhere!
Popeyed scorpionfish found in Kashiwajima.

Season Calendar for Divers

Diving Areas

Uguru Island

There are also dive sites near the underwater observatory, seen in the distance in the photo.
Uguru Island

A small island located north of Okinoshima Island. The surrounding ocean has a limitless supply of delights, with a wide cast of characters, including big fish, schools of pelagic fish, and tropical fish! Uguru Island also offers the best chance in all of Shikoku to encounter sea turtles, large pelagic fish such as dogtooth tuna, and bigeye trevally. Some lucky people have caught sight of manta rays and hammerhead sharks here, and you have a great chance to run into schools of dolphins on your way back from the dive site.

Okinoshima Island

Cavern diving at Kuroiwa.
Watching fish and coral in Okinoshima.

Located just beyond Kashiwa Island, Okinoshima can be reached from Sukumo by ferry. The warm Kuroshio Current hits the island directly, keeping transparency relatively high throughout the year, and there are plenty of fish and coral to be seen in the waters. Throughout the year, you may catch a glimpse of popular macro creatures such as the pigmy seahorse and white-rayed shrimpgoby, as well as other tropical fish brought to the island by the current. If you are really lucky, you may be able to encounter a thresher shark.


Surrounded by hundreds of sharks!
Bulgyhead wrasse live in the waters from the southern part of Japan to the South China Sea.

Otsuki is a town located in the southwesternmost part of Kochi prefecture, the surrounding area of which is well-known for whale watching. The town’s borders include Kashiwa Island, and sometimes divers come from the island to visit the dive site at Tsutome-zaki. The town’s dive shops are located at Tachibanaura, Amaji, and Issai. There are many dive sites along the coast, where you may find many creatures such as bulgyhead wrasse, elegant firefish, and wrought iron butterflyfish.

Kashiwa Island

Beard grunt at Ohne.
Red lionfish swimming elegantly through the beautiful soft coral of Kashiwajima.

The waters around Kashiwa are known among divers in Japan for their rich marine biodiversity with many coral reefs and tropical creatures such as ribbon eel and paintpot cuttlefish, as well as marine life from temperate oceans. Ushironohama, in the northern part of Kashiwa, is one of the main dive sites of this area. This gorgeous dive site looks as if it were a traditional Japanese garden created underwater. Drop-offs and arches are also worth mentioning, but the surprising variety of fish is what makes Kashiwa special; it is said that there are over 1,000 kinds of fish inhabiting around the waters of Kashiwajima.


School of silver-stripe round herring.

Tatsukushi is home to Tatsukushi Marine Park, Japan’s first national marine park. There are dive sites scattered around the east side of its Cape Chihiro, located between Cape Ashizuru and Otsuki Peninsula. Schools of fish grow larger from summer to autumn, especially those of greater amberjack, rainbow runner, damselfish and anthias. Winter through spring is ideal for nudibranch watching; more than 100 kinds of nudibranch are observed in Tatsukushi during this season.


Friendly bulgyhead wrasse called “Yoriko”.
A small pigmy seahorse hiding in a sea fan.

Cape Ashizuri, the southernmost point of Shikoku, is greatly affected by the Kuroshio Current. Large pelagic fish are often observed around the giant rock reefs, as well as colorful tropical fish carried to Ashizuru by the current. There are also many popular creatures such as pigmy seahorses and ribbon eels.

Yaiga, Shiwa, Okitsu

A little frogfish resting on a sponge.

Relatively new dive areas that have become easier to access thanks to the Kochi Expressway. Pelagic fish such as greater amberjack and Japanese amberjack may be observed. There are also many tropical fish carried to this area by the Kuroshio current, creating tropical-like waters.


The sun sets over the waters of Okinoshima.
Tunnels and artificial reefs are fun to explore.

Muroto’s unique ocean landform has earned it designation as a UNESCO Global Geopark. The Kuroshio current hits Cape Muroto, on the southernmost point of the east side of Shikoku, creating highly transparent blue water and dynamic landforms and nurturing a community of large pelagic fish and soft coral. There is also a good chance that you will encounter popular creatures such as sea turtles here. Muroto is also known for its artificial fish reef of about 30 artificial fish reefs, each about three square meters, that attract various fish.


The sun sets over the waters of Okinoshima.
A whitespotted bambooshark egg.

Kannoura is an area located between Tokushima and Kochi prefectures where you can enjoy gorgeous view of beautiful soft and hard coral and colorful reef fish thanks to the branch of the Kuroshio Current that flows here. Local dive sites are a beginner-friendly distance from the port, located around Kazura Island and Akaba Island. Kannoura is the only place in Japan where the mating of whitespotted bamboosharks can be observed in the spring.