| Middle Branch Grass River | |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Subdivision Type2: | State |
| Subdivision Name2: | New York |
| Source1: | Pleasant Lake Stream, Blue Mountain Stream |
| Mouth: | Grass River |
| Mouth Location: | Clare, New York |
| Mouth Coordinates: | 44.3758°N -75.0608°W |
| Mouth Elevation: | 799feet |
| Basin Size: | 63sqmi |
| Tributaries Left: | Tracy Brook |
| Tributaries Right: | Deerskin Creek, Mud Brook, Bear Creek, Alder Brook |
The Middle Branch Grass River flows into the Grass River in Clare, New York. The Middle Branch Grass River and South Branch Grass River combine together here and become the Grass River.[1]