The Crown in Whitebrook scooped top prize in Wales' annual True Taste Food and Drink Awards.
The privately-owned restaurant is the only one in Wales to boast a Michelin star, having earnt one in January 2007.
General manager David Hennigan said the award reflected the hard work put in by staff.
"The reason for our winning is two-fold," he said. "We are working with excellent staff and sourcing excellent food and drink. Everybody works as hard as each other."
Hennigan praised the Crown's "talented" head chef, James Sommerin for his "own personality" twist to the modern British menu with French influences.
Since joining two years ago, Hennigan said the restaurant had not changed essentially, but he would "like to think it has got better".
"Over a period of years people recognise consistency and quality," he said.
He described the fine-dining atmosphere as "professional, but approachable and friendly".
Hennigan does not plan to make any radical changes to the Crown but insists that it will continue to source fresh produce.
The staff have their fingers crossed for a Michelin star to be awarded for the fourth year running next January.
Evan Evans Brewery were also victorious at the awards, coming top in the alcoholic drink section.