| Brețcu | |
| Pushpin Map: | Romania |
| Subdivision Type1: | Country |
| Subdivision Name1: | Romania |
| Subdivision Type2: | Counties |
| Subdivision Name2: | Covasna County |
| Subdivision Type3: | Villages |
| Subdivision Name3: | Brețcu |
| Length: | 13km (08miles) |
| Source1: | Nemira Mountains |
| Mouth: | Râul Negru |
| Mouth Location: | near Lunga |
| Mouth Coordinates: | 46.0328°N 26.2438°W |
| Basin Size: | 47km2 |
| Tributaries Left: | Pârâul Întortochiat, Mărtănuș |
The Brețcu (Hungarian: Bereck) is a left tributary of the Râul Negru in Romania. The 13km (08miles) long river flows into the Râul Negru east of Lunga.[1] Its basin size is 47km2.