Izu Ōshima is the most accessible of the Izu Islands, and nearly all of its diving is from the beach, at five points set by agreement with the island fishery cooperative. Lava has left arches, channels and columnar-jointed walls hung with soft corals, and the Kuroshio Current keeps the water warm. Akinohama is the photographers’ beach, Keikai draws hammerhead schools at sunrise in summer and early autumn, and scooter routes reach Triple Arch and the Akinohama Drop-off.
About diving in Izu Ōshima
Diving here is almost entirely from the beach, and divers cannot go in just anywhere: five points are set by contract with the Oshima fishery cooperative, and scooter routes run further offshore from them. A usual day is two dives at calm points with a break by the sea, and a third dive, a night dive or a sunrise hammerhead dive can be added. Even in strong winds or a typhoon, diving is often possible on a sheltered side of the island. Akinohama is entered off a natural lava jetty and left by a ladder.
The island is a volcano, and the lava shows underwater as arches, channels, crevices and columnar-jointed walls, decorated with colourful soft corals. Keikai’s channel walls hide nudibranchs, seahorses and blennies, Toshiki mixes hard and soft corals with anemonefish, and Ōnohama has table corals. Offshore, the scooter drop-off is a wall covered in soft corals with anthias swarming over it, and from summer into autumn schools of grunts fill the arches.
Beginners and students do well here. A sheltered side is often diveable, which makes the island a popular place for courses, Nodahama stays within 12 m, and the Akinohama ladder makes entry and exit easy for divers of all levels. The scooter sites go further out, and the hammerhead wait at Hammer Scramble is deep enough to make it a site for advanced divers.
Best time to dive Izu Ōshima
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Good | Good | Good | Good | Good | Good | Prime | Prime | Prime | Prime | Good | Good |
From autumn through winter the island fills with tropical fish, and winter clarity rivals Okinawa. The water is at its coldest around the start of March. In April there may be no ferries at all, leaving only planes and jetfoils. Hammerhead schools arrive at Keikai and Hammer Scramble from mid-June, and summer fills the arches at Nodahama and Triple Arch with grunts while hirome seaweed carpets the floor at Ōnohama. The water peaks in mid-August, and the hammerhead window closes in mid-October.
Dive types & marine life
Hammerhead schools come at sunrise from mid-June to mid-October, at a set time and place, so encounters on the scooter route are likely. Thresher sharks visit Akinohama from summer into autumn and are most reliable on autumn early mornings at the drop-off. Green turtles turn up on nearly every dive.
- Reef
- Wall
- Night
- Hammerheads
- Thresher sharks
- Sea turtles
- Nudibranchs
- Macro critters
- Reef fish swarms
Best dive sites in Izu Ōshima
- 1
Akinohama
The island’s most popular beach, a macro ground with boulders, sand, slopes and walls.
- 2
Keikai
Maze of soft-coral channels where hammerhead schools pass at sunrise in season.
- 3
Hammer Scramble
Scooter-only route on a hammerhead path, with the wait on a rock at 20 m.
- 4
Ōnohama
Columnar-jointed walls where green turtles turn up on most dives.
- 5
Nodahama
Gentle, shallow beach under a lava arch hung with soft corals.
- 6
Triple Arch
Three arches side by side on a scooter route, packed with grunt schools in summer.
- 7
Akinohama Drop-off
Scooter-only wall where pelagics hunt the fish schools off its tip; scooter licence required.
- 8
Toshiki
Southern-tip beach with deep-cut channels and columnar-jointed walls.
Site guides
Reef
Endemic Japanese pygmy seahorses off a lava-jetty shore entry
How to get to Izu Ōshima
ANA flies from Haneda in 35 minutes to an airport close to Motomachi. Jetfoils take about 45 minutes from Atami and about one hour 45 minutes from Takeshiba in Tokyo, and ships land at Okata or Motomachi depending on the sea. Divers can be met by their shop at the day’s arrival port.
Dive videos
Scuba Diving in Ōshima Jun 2024 · Kiksy ♡ on YouTube
Questions divers ask
Is the diving at Izu Ōshima from boats or the beach?+
Almost all of it is from the beach, at five points set by agreement with the island fishery cooperative. A few shops use underwater scooters to reach sites further offshore.
What does a diver need for the hammerhead sites?+
Keikai is a beach entry where the schools pass at sunrise in season. Hammer Scramble is reached only by underwater scooter, and its wait on a rock at 20 m makes it an advanced dive. The Akinohama Drop-off, where hammerheads also appear at times, is open only to divers with a scooter specialty.
Is guiding available in English?+
Not at every shop. At least one shop on the island does not guide in English, so divers without Japanese should confirm the language before booking.
Sources
Embed
Run a dive centre, club or blog? Embed this map of 5 dive sites near Izu Ōshima on your own page.
Similar destinations
East Asia
A sunken shrine, Shark City and Japan's cod hole at the mouth of Tokyo Bay
Mainland Japan's only reliable schooling hammerhead dive
East Asia
Amami Ōshima
Japan
Pufferfish sculpt two-metre geometric nests into the sand at 25 m
Shore-entry coral slopes at the warm southern tip of Taiwan