Britain will become one of only two countries allowed to export live langoustines to China under a new agreement announced by Liam Fox.
Also known as Dublin Bay Prawns, exports of the shellfish could be worth up to £26.5 million over the next five years, the Department for International Trade said.
The Scottish and Northern Ireland fishing sectors could to receive a £5.3 million export boost per year as a result of the deal.
Exports of frozen langoustines are already in place.
International Trade Secretary Liam Fox said the deal was a “key milestone” for the sector and shows a “clear demand for the world-class quality of British seafood”.
“This is a key milestone for the sector and demonstrates the great work my international economic department is doing to deliver enhanced market access for a variety of British produce.
“Now more than ever UK businesses should be exploring opportunities for selling their products overseas.
“Today’s announcement is just once example of the opportunities available for British businesses looking to grow beyond Europe.”
David Larrad, chief executive of the Shellfish Association of Great Britain (SAGB) added: “The UK has some of the finest quality of shellfish in the world and to satisfy demand, especially at this time of uncertainty with European markets, the SAGB looks forward to working with government, and its agencies, in the future to establish new markets and more trade agreements to benefit the shellfish industry.”