| Râul Lacului | |
| (Lacul River) | |
| River | |
| Countries | Romania |
|---|---|
| Counties | Sibiu County |
| Tributaries | |
| - right | Valea Luntrei |
| Source | |
| - location | Lotru Mountains |
| - elevation | 1,007 m (3,304 ft) |
| - coordinates | |
| Mouth | Sadu |
| - elevation | 537 m (1,762 ft) |
| - coordinates | |
The Râul Lacului or Lacul River is a tributary of the Sadu River in Romania.