Experts found the bar outside the walls of the fort at Stracathro, near Brechin.
It was at one end of a line of watchtowers and bases stretching south to Doune, near Stirling, and known as the Gask Ridge.
The forts are thought to date from around 70 AD, about 50 years before Hadrians Wall was built.
The University of Liverpool team found the wine bar in a vicus, or small civilian settlement, using a variety of techniques, including metal detecting.
We hadnt expected to find a pub her
They say the Roman watering hole had a large square room, the equivalent of a public bar, and fronted on to a paved area, not unlike a modern beer garden. The team also found the spout of a wine jug.
Dr Birgitta Hoffmann, co-director of The Roman Gask Project, said: Roman forts south of the Border have civilian settlements that provided everything they needed from male and female companionship to shops, pubs and bath houses.
It was a very handy service, but it was always taught that you didnt have to look for settlements at forts in Scotland because it was too dangerous. Civilians didnt want to live too close.
We hadnt expected to find a pub here.
It shows the Romans and the local population got on better than we thought. They would have lived in harmony here.
Stracathro is thought to have housed various units of the Roman army, perhaps a total of around 700 men. It was probably abandoned by 90 AD as the Romans vacated all their fortifications north of the River Forth.
The discovery casts doubt on the idea that there was a perpetual state of conflict between the Picts and the Romans.
This image was popularised by the story of the Ninth Legion, the Roman unit said to have been wiped out after marching into Scotland in 117 AD on a mission to put down the northern barbarian hordes.
Via Ancient Picts liked to pop down the legion for a pint | UK News | Express.co.uk - Home of the Daily and Sunday Express