Their detention is the latest following a series of recent police operations intercepting huge quantities of drugs on yachts.
In all cases the suspects have been transferred to France, but this time the suspects - two Dutchmen and a Pole - will face the court in French Polynesia.
The three arrived in a catamaran in Nuku Hiva in the Marquesas islands from Costa Rica.
The prosecutor said the men said they didn't know they had 500 kilogrammes of cocaine on board.
He said the drugs were probably destined for the Australian market.
This year more than two tonnes of cocaine have been seized on yachts stopping in French Polynesia.