| Rezu Mare | |
| Pushpin Map: | Romania |
| Subdivision Type1: | Country |
| Subdivision Name1: | Romania |
| Subdivision Type2: | Counties |
| Subdivision Name2: | Harghita |
| Length: | 16km (10miles) |
| Source1: | Giurgeu Mountains |
| Mouth: | Putna |
| Mouth Location: | near Tulgheș |
| Mouth Coordinates: | 46.936°N 25.7499°W |
| Progression: | Putna→ Bistricioara→ |
| Basin Size: | 47km2 |
| Tributaries Left: | Pârâul Vacii, Roșu Mare, Pârâul lui Grigore, Beneș, Jang |
The Rezu Mare is a left tributary of the river Putna in Romania. It flows into the Putna near Tulgheș. Its length is 16km (10miles) and its basin size is 47km2.