Biertan (German: Birthälm; Transylvanian Saxon dialect: Birthälm/Bierthalmen/Bierthalm; Hungarian: Berethalom) is a commune in Sibiu County, Transylvania, Romania.

Biertan is one of the most important Saxon villages with fortified churches in Transylvania, having been on the list of UNESCO World Heritage Sites since 1993.

The village settlement quickly developed into an important market town and by 1510 Biertan supported a population of about 5,000 people.

It is one of the most visited villages in Transylvania, being the historically important place of the annual reunion of the Transylvanian Saxons, many of whom now live in Germany.

The "Luna Plină" ("Full Moon") Horror and Fantasy Film Festival takes place in Biertan.