The accident happened on Ahe atoll in the Tuamotus, killing a highly experienced diving instructor Gilles Demee.
He was accompanied by two Tahiti-based Russian academics, Alexey Zykin and Tatiana Makarova.
The circumstances of the accident are not clear and an investigation has been launched.
Reports say the three bodies have been located but are yet to be recovered.
Photo: SUPPLIED / Danica Stent, DOC Diving accident claims three lives in cave of Ahe atoll
