The underwater world of Con Dao
Con Dao’s marine ecosystem is one of the most diverse and well-preserved in Vietnam, making it a top destination for divers looking for both vibrant coral reefs and rare marine species. Protected under Con Dao National Park, the waters surrounding the archipelago boast over 340 species of coral, 202 species of reef fish, and a variety of marine mammals, including the endangered dugong. Divers can expect excellent visibility, particularly during the best diving season, with depths ranging from shallow reef gardens perfect for snorkeling to deeper sites where larger pelagic species roam.
A marine biodiversity hotspot
The waters around Con Dao are home to some of the richest marine biodiversity in Vietnam, including a high concentration of rare and endangered species. Many of these species are listed in the IUCN Red List, making the area one of Vietnam’s most important marine conservation zones. With over 1,000 hectares of coral reef, Con Dao supports a complex ecosystem that serves as a nursery for marine life across Southeast Asia.
Notable marine life in Con Dao includes:
- Tropical reef fish – clownfish, angelfish, butterflyfish, and parrotfish
- Larger species – barracuda, cobia, groupers, and rays
- Marine mammals – blue whales, Indo-Pacific finless porpoises, and dugongs
- Sea turtles – green turtles, hawksbill turtles, and leatherbacks
- Rare crustaceans and mollusks, many of which are endemic to the region
Unique dive sites and marine features
Beyond its coral reefs, Con Dao’s underwater landscape features dramatic rock formations, caves, and even a shipwreck dive site, offering a variety of diving experiences for both beginners and experienced divers. The protected status of the marine park means that Con Dao’s reefs remain largely untouched, with minimal environmental impact from tourism compared to other dive sites in Vietnam.
One of the biggest draws for divers is the chance to encounter the elusive dugong, a rare marine mammal that relies on Con Dao’s seagrass beds for survival, however very rare to see. The island is also one of the most important nesting grounds for sea turtles in Vietnam, with a chance of spotting them while diving.
With its pristine conditions, diverse marine life, and strong conservation efforts, Con Dao offers one of the best diving experiences in Vietnam.
Diving in Con Dao compared to other places in Vietnam
While Nha Trang, Phu Quoc, and Cham Islands are well-known diving destinations in Vietnam, Con Dao stands out for its pristine marine environment and strong conservation efforts. The coral reefs here are healthier and less impacted by tourism, making it an ideal destination for divers looking for an unspoiled underwater world.
- Nha Trang: Offers accessible and budget-friendly diving, but the reefs in Hon Mun Marine Park have suffered from overcrowding and coral damage. Con Dao provides better biodiversity, clearer waters, and fewer divers per site.
- Whale Island: A quieter alternative to Nha Trang with some healthy coral gardens, but with fewer dive sites compared to Con Dao’s 25+ dive spots.
- Phu Quoc: Known for easy, shallow dive sites, but marine life is less abundant due to overfishing and plastic pollution. Con Dao offers better visibility and more diverse marine species.
- Cham Islands (Hoi An): Has a protected marine park, but visibility can be inconsistent due to river sediment, and biodiversity is not as rich as Con Dao.
Overall, Con Dao offers the best diving experience in Vietnam for those seeking a quiet, well-preserved marine environment with diverse marine life.
For a detailed comparison of diving destinations in Vietnam, check out our full guide: Diving in Vietnam
Best diving season for Con Dao
High season
The best time for diving in Con Dao is from March to September, when the seas are generally calm, warm, and clear. Even though this period overlaps with the rainy season (especially July to September), showers are usually short-lived and occur in the afternoons or evenings, meaning mornings remain perfect for diving. During this time, visibility can exceed 20 meters, making it ideal for exploring the reefs and marine life.
Low season
From November to February, the stronger winds bring rougher seas, making diving more challenging. However, sheltered dive sites still offer good opportunities on calmer days. The advantage of diving in low season is fewer divers and more solitude at dive spots, but conditions vary, and visibility may be lower than in peak months. With 25+ dive sites around the Con Dao archipelago, there’s usually somewhere suitable to dive year-round depending on the weather.
Weather and climate in Con Dao
Con Dao has a tropical monsoon climate with two distinct seasons:
- Dry season (November to April): Characterized by little rainfall, lower humidity, and calm seas, this period offers ideal beach conditions. However, stronger winds from November to February can create choppier waters, affecting diving visibility.
- Rainy season (May to October): While this period brings higher humidity and short, heavy rain showers, the seas are often calm in the mornings, making it the best time for diving.
Since the best diving season overlaps with the rainy season, those looking to combine diving with a beach holiday should visit in March, April, or early May, when both diving and beach conditions are optimal.
For a more detailed guide about the weather in Con Dao, read our guide: best time to visit Con Dao.
Best dive sites in Con Dao
Con Dao offers an impressive selection of 25 dive sites, each with its own unique underwater landscapes and marine life. From shallow coral reefs to deep wreck dives, there’s something for divers of all levels. The choice of dive site often depends on the season and weather conditions, but thanks to the variety of sites, there is always a great spot to explore. Here are some of the most notable dive sites in Con Dao:
Hon Cau – Best visibility & diverse coral formations
- Located 20–30 minutes by speedboat from the main island, Hon Cau is known for its clear waters, with visibility often exceeding 20 meters.
- Features branching corals, hard coral gardens, and a dead coral field that attracts nudibranchs and sea slugs.
- Marine life includes giant barracuda, trevally, bamboo sharks, and turtles.
- Best for: Divers looking for excellent visibility and a diverse coral ecosystem.
Hon Bay Canh – Best for beginners & calm conditions
- Just 10–15 minutes from Con Dao, Hon Bay Canh offers calm waters and is one of the best spots for beginner divers.
- The site features table coral, branching coral, and an abundance of reef fish such as clownfish, butterflyfish, eels, and cuttlefish.
- It is also an important turtle nesting site, with protected areas where sea turtles lay eggs.
- Best for: Beginners, photographers, and those interested in marine conservation.
Hon Tai (Lucky Island) – Pristine reefs & large fish schools
- Only 5–10 minutes away, this site is known for its high fish population and rarely visited reefs.
- You can find schools of barracuda, snappers, batfish, parrotfish, and giant pufferfish.
- Visibility here is unpredictable, with conditions changing quickly from clear to murky.
- Best for: Divers who want to see large fish schools and explore less crowded dive sites.
Fish Highway – Con Dao’s Shipwreck Dive
- A sunken fishing boat has transformed into an artificial reef, attracting marine life such as sponges, scorpionfish, stonefish, and moray eels.
- Depth ranges from 20 to 28 meters, making it ideal for advanced divers.
- Best for: Wreck diving and observing unique reef formations.
Hun Trung – Strong currents & big Pelagic Fish
- Known for strong currents, Hun Trung is an exciting challenge for advanced divers.
- Large schools of tuna, barracuda, and even dolphins and sharks have been spotted here.
- Best for: Experienced divers with currents and chance of big marine life.
White Rock – Vibrant coral walls & Manta Rays
- A deep dive site with soft corals, tropical fish, and occasional manta rays.
- Only recommended for experienced divers in calm conditions due to strong currents.
- Best for: Soft coral lovers and advanced divers looking for a rare manta ray sighting.
Each of these sites offers a unique diving experience, whether you’re looking for calm waters and colorful coral reefs or deep dives with strong currents and big fish.
Diving options in Con Dao
Con Dao offers a variety of diving opportunities, catering to both beginners and experienced divers. Whether you’re interested in trying an introductory dive, joining a guided trip to explore the best dive sites, or getting a professional PADI certification, there are options to suit all levels. The island’s clear waters, diverse marine life, and well-preserved coral reefs make it an excellent destination for different types of diving experiences.
Introduction Dives – First-time diving experience
Introductory dives are perfect for those with no prior diving experience. These dives do not require certification, as they are conducted under the supervision of professional instructors in calm, shallow waters. This allows first-time divers to safely explore Con Dao’s beautiful coral reefs while experiencing the unique sensation of breathing underwater. It’s an ideal option for tourists who want a short yet memorable diving experience without committing to a full certification course.
Dive trips for certified divers
Certified divers can join organized dive trips that visit the best dive sites around Con Dao. These trips offer a mix of single and multi-day diving experiences, usually consisting of two dives per session. Depending on the conditions and diver preferences, trips may include locations like Hon Cau, Hon Bay Canh, and Fish Highway. With depths ranging from 10 to 28 meters, these dives are suitable for both recreational and advanced divers looking to explore Con Dao’s rich underwater biodiversity.
Freediving and shore diving
For those who prefer diving without a tank, freediving is an exciting alternative. Con Dao’s calm, clear waters make it an ideal location for practicing breath-hold techniques and exploring marine life up close. Additionally, shore diving is available at select sites, allowing divers to enter the water directly from the beach and explore reefs without the need for a boat. These options offer a different way to experience Con Dao’s underwater world with minimal equipment.
PADI certification courses
For those planning a longer stay on the island, Con Dao offers PADI certification courses for both beginners and advanced divers. The Open Water Diver course is perfect for those looking to get their first certification, while advanced and specialty courses are available for experienced divers wanting to refine their skills. Taking a certification course in Con Dao provides the advantage of small training groups, professional instruction, and access to some of Vietnam’s best-preserved dive sites.
Recommended diving centers
Con Dao has a much smaller diving scene compared to places like Nha Trang or Phu Quoc, but that also means fewer crowds and a more relaxed experience. There aren’t many dive centers to choose from, but the main one operating here is Con Dao Dive Center, which has built a solid reputation among divers.
Con Dao Dive Center
Con Dao Dive Center is the most established dive operator on the island, offering PADI-certified courses, fun dives, and snorkeling trips. Run by Phong and Danny, the center is known for its small group sizes, ensuring a more personal diving experience compared to busier destinations like Nha Trang or Phu Quoc. They operate trips to various dive sites around Con Dao, adjusting locations based on weather conditions to provide the best visibility and marine life encounters.
The center offers beginner-friendly introductory dives, guided dives for certified divers, and full PADI certification courses. During the high season, multiple dive trips are available daily, and in the low season, Phong continues to run operations while Danny relocates to Phu Quoc. With well-maintained equipment and a reputation for professional guidance, Con Dao Dive Center is the go-to option for diving on the island.
Flying after diving
If you are an experienced diver, you probably already know that you should not fly too soon after diving. The general recommendation from Divers Alert Network (DAN) is to leave a 24-hour surface interval before flying after any type of diving to reduce the risk of decompression sickness. You can check the official guidelines for flying after diving here.
Since Con Dao is a remote island, the most common way to travel to and from the island is by flight. While there are boats to Tran De (near Soc Trang) in the Mekong Delta, this route is not convenient unless you are combining Con Dao with a Mekong Delta trip. Most travelers fly to and from Ho Chi Minh City or other mainland destinations, so make sure your flight schedule does not interfere with your diving plans.
Additional tip: Get proper insurance
Given Con Dao’s remote location and limited medical facilities, it is highly recommended that divers have insurance covering diving accidents and emergency evacuation. Not all standard travel insurance policies include diving coverage, so double-check your policy and consider purchasing additional diving insurance if necessary.
