This means that only fish sauce produced on the island of Phu Quoc can use this label in the 28 nations of the European Union.
The PDO covers agricultural products and foodstuffs which are produced, processed and prepared in a given geographical area using recognised know-how.
It is one of three EU schemes designed to promote and protect the names of quality agricultural products and foodstuffs.
Phu Quoc fish sauce is made from locally harvested anchovies using a traditional recipe. It is a popular condiment in Vietnam, and has long been famous for its special flavour.
The addition of the PDO stamp is expected to boost sales of this Vietnamese speciality in the European Union, said Nguyen Thi Tinh, President of the Phu Quoc Fish Sauce Association.
Head of the EU Delegation in Vietnam Franz Jessen said that the protected status will increase the product’s value and benefit Vietnamese producers.
However, local producers face a shortage of raw materials, as anchovy numbers have dwindled from excessive harvest.
The shortage is also caused by competition from non-local buyers who purchase at higher prices to sell to Chinese merchants.
Phu Quoc currently has over 80 fish sauce producers with an annual output of 20 million litres.