Currently five Irish pig processing establishments had been accredited to produce pork for export to the country.
Simon Coveney, Ireland’s minister for agriculture, food and the marine, said he welcomed the opening of the market and that the agreement provided the Irish pigmeat sector "with a vital foothold in this key market".
"Vietnam is an important market in south-east Asia, with a growing population, and there are good prospects for Irish meat exports both in the short and long term," he said.
"I am hopeful the decision of the Vietnamese authorities will also have a positive effect on our efforts to gain access to other markets in the region."
He said that, at a time when there have been difficulties for Ireland with the Russian market since the start of the year, it was vital Irish companies had access to as many global markets as possible.
"My department is continuing to work closely with European partners to try to restore the trade in pigmeat with Russia. In the meantime, we will continue to prioritise the opening of new third-country markets for Irish agri food products, working with the Department of Foreign Affairs and Trade and Bord Bía to provide new market opportunities for Irish companies."