| Rujan | |
| Elevation M: | 968 |
| Elevation Ref: | [1] |
| Map: | Serbia |
| Map Size: | 250 |
| Location: | Serbia |
| Coordinates: | 42.3661°N 21.8183°W |
Rujan[1] (Serbian: Рујан) or Rujen (Serbian: Рујен), is a mountain in southern Serbia, near the town of Bujanovac. Its highest peak Kalje has an elevation of 968m (3,176feet) above sea level. On the mountain, there is Kale-Krševica archeological site, dating from the 13th century BC. The Pčinja flows through the valley of Rujen.