The fishermen from Pudukottai District were arrested on October 5 on the charge of fishing in Sri Lankan waters and remanded to judicial custody.
The five were produced before a Sri Lankan court which ordered their release, Pudukottai Assistant Director of Fisheries Sekar said.
Some other fishermen from Rameswaram, arrested by Sri Lankan Navy, were expected to be released in a day or two, officials here said.
The releases of five fishermen coincided with the talks between fishermen associations of India and Sri Lanka in New Delhi today on the vexed issue of fishing rights in the Palk Strait.