They were arrested on Wednesday at two locations, Xinhua news agency cited the Sri Lankan Navy as saying.
Two fishing trawlers were also seized in the seas northwest of Analathivu Island and the area north of Mannar, an official statement said.
Sri Lankan Fisheries Minister Mahinda Amaraweera has said Indian fishermen will continue to be arrested if they poach in the island nation’s waters.
Amaraweera said the government was seeking to resolve the Indo-Lanka fishing dispute in a diplomatic manner and talks would be held regarding this next month.
A Tamil Nadu fisherman was killed earlier this month, allegedly by the Sri Lanka Navy. But Colombo says its Navy was not involved in the incident.