The ban was on motor boats, trawlers and mechanised fishing boats, a notification issued by the Fisheries department said.
The ban on the 20 km stretch of the Dhamra-Rushikulya river mouth was clamped in accordance with Sections 2, 7 and 4 of the Orissa Marine Fishing Regulation Act, 1982.
It was also applicable to the beaches of Gahirmatha, Rushikulya and Devi where patrols would ensure the ban.
Fishermen were unhappy over the ban and said conservation of the turtles should not be at the cost of their livelihood.
Bank-funded Integrated Coastal Zone Management Programme has taken up alternative livelihood projects.
Despite the ban and conservation measures, a large number of turtles get killed every year in fishing nets and in collisions with trawlers and boats.