Carmarthen Ham has been awarded protected name status by the EU, its producers have said.
The meat now has protected geographical indication (PGI) status, which is one of three protected food name designations.
Brothers Chris and Jonathan Rees, the latest of five generations to produce the ham, said they were "over the moon".
"It's six years down the line, and we had a bit of a scare with this Brexit, but we've finally got there", said Mr Rees.
The Commission describes Camarthen Ham as an air-dried, salt-cured ham made from pig legs with a characteristic delicate aroma typical of air-dried ham.
The ham disintegrates when pulled and has a silky soft texture.
Welsh beef, Melton Mowbray pork pies, and Jersey Royal potatoes are among the UK protected food names worth a combined £1 billion.
"Wales is a huge source of pride Britain's food and drink sector - from Halen Mon sea salt in the north to Pembrokeshire new potatoes in the south - it is home to some of the country's culinary big-hitters", said a Defra spokesperson.
However, Brexit has placed a question mark over the future of EU's PGI labeling system.
The status prevents manufacturers from outside a region copying a regional product and selling it as that regional product.
