| Harțag | |
| Pushpin Map: | Romania |
| Subdivision Type1: | Country |
| Subdivision Name1: | Romania |
| Subdivision Type2: | Counties |
| Subdivision Name2: | Buzău County |
| Length: | 8km (05miles) |
| Source1: | Buzău Mountains |
| Mouth: | Buzău |
| Mouth Coordinates: | 45.5613°N 26.179°W |
| Basin Size: | 36km2 |
| Tributaries Left: | Ceapa, Hărțăgel |
| Tributaries Right: | Pascu |
The Harțag is a left tributary of the river Buzău in Romania. Its source is in the Buzău Mountains. It flows into the Buzău downstream from Crasna. Its length is 8km (05miles) and its basin size is 36km2.