| Type: | Ortsteil |
| Town: | Hohenberg-Krusemark |
| Coordinates: | 52.7447°N 12.0331°W |
| State: | Sachsen-Anhalt |
| District: | Stendal |
| Verwaltungsgemeinschaft: | Arneburg-Goldbeck |
| Plantext: | Location of Altenzaun in Stendal district prior to its merger into Hohenberg-Krusemark |
| Elevation: | 26 |
| Area: | 11.12 |
| Population: | 127 |
| Stand: | 2006-12-31 |
| Postal Code: | 39596 |
| Area Code: | 039394 |
| Licence: | SDL |
| Website: | www.altenzaun.de |
Altenzaun is a village and a former municipality in the district of Stendal, in Saxony-Anhalt, Germany. Since 1 January 2009, it is part of the municipality Hohenberg-Krusemark.