Altdorf, which is German for old village, may refer to:
In Switzerland:
- Altdorf, Jura, an little used German name for the village of Bassecourt in the canton of Jura
- Altdorf, Schaffhausen, a village in the canton of Schaffhausen (generally written as "Altdorf SH"),
- Altdorf, Uri, the capital of the canton of Uri (sometimes written as "Altdorf UR"),
In Germany:
- Altdorf bei Nürnberg, a city in Bavaria, home of the (former) University of Altdorf
- Altdorf, Lower Bavaria, a municipality in the district of Landshut, Bavaria
- Altdorf, Böblingen, a town in the district of Böblingen, Baden-Württemberg (Altdorf bei Böblingen)
- Altdorf, Esslingen, a municipality in the district of Esslingen, Baden-Württemberg (Altdorf bei Nürtingen)
- Altdorf, Rhineland-Palatinate, a municipality in the district Südliche Weinstraße, Rhineland-Palatinate
- Altdorf, the name of Weingarten (Württemberg) until 1865
In France:
- Altdorf, Bas-Rhin, village in the Bas-Rhin department (Alsace), near Strasbourg
Other:
- Altdorf (Warhammer), the capital of The Empire in the fictional universe of Warhammer Fantasy