About 400 fishermen were on fast and boycotting fishing since November six demanding release of their fellow colleagues detained in Sri Lanka on the charge of fishing in the island nation's waters.
Victor (42) died at the fasting venue following the heart attack, officials said.
Meanwhile, Velmurugan, another fisherman, whose boat had been seized by the Lankan Navy a few weeks ago while fishing, died at his house after he suffered a massive heart attack last night.