Con Dao's diving is defined by its resident Green Sea Turtle population, which appears across every site and makes it one of the most reliable places in Vietnam to dive alongside them. Batfish and White-spotted Puffer are equally ubiquitous, while Great Barracuda patrol the mid-water with regularity. Occasional encounters with Whale Shark and Dugong add real weight to any dive plan. Visibility varies considerably depending on season and exposure, so conditions shape site choice as much as marine life does. Water stays warm throughout the year, peaking from late spring through summer.
Monthly water temperature across Con Dao's sites, from satellite sea-surface data corrected for depth. The band shows the site-to-site spread.
Water temperatures are at their warmest from late spring through to autumn, and the best-months data points strongly to March through May as the peak window for calmer conditions and clearer water. Visibility can swing widely across the year, so exposed sites are best approached during the settled season. The cooler months from January to February and again in late November and December see reduced diver activity, which may suit those preferring quieter reefs.
10 more sites to explore
Water temperature around Con Dao ranges from about 26°C in January to 30°C in May, based on satellite sea-temperature data for its dive sites.
In the warm season (about 30°C) a rash guard or 3mm shorty is comfortable in Con Dao; in the coldest months (about 26°C) step up to a 3mm full suit.
Fin maps 10 sites in Con Dao (10 scuba diving sites).
Green Sea Turtle is observed across all sites and is the signature encounter. Batfish and White-spotted Puffer are similarly widespread. Great Barracuda, Whale Shark, Cobia and European Parrotfish appear with varying frequency, while rarer finds include Dugong, Ghost Pipefish, Blue-ringed Octopus, Grey Reef Shark, Whitetip Reef Shark, Eagle Ray and Spanish Dancer, all observation-backed from the sites.
The site mix across Con Dao includes reefs that can be dived at a range of skill levels, though visibility and conditions vary considerably through the year. Exposed sites during unsettled periods are better left to more confident divers. Planning around the calmer spring window improves the experience for those building their open-water hours.
Water temperature remains warm throughout the year, rising further from late spring into summer. The best-months data clusters strongly around March to May, when conditions are most settled and visibility tends to be at its best. Later in the year, from June through September, diving remains active though exposure and swell can be more variable. The quietest period falls around January and February.
Whale Shark has been observed across a notable portion of Con Dao's sites and is classed as an occasional sighting. Encounters are not guaranteed on any given dive, but the species appears with enough regularity to be considered a realistic possibility rather than a rare outlier. Timing a visit to the peak season improves overall underwater visibility and the broader quality of each dive.
