| Martin Brook | |
| Pushpin Map: | New York |
| Pushpin Map Caption: | Location of the mouth of Martin Brook |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Subdivision Type2: | State |
| Subdivision Name2: | New York |
| Subdivision Type4: | County |
| Subdivision Name4: | Otsego |
| Source1 Coordinates: | 42.3614°N -75.32°W |
| Mouth: | Susquehanna River |
| Mouth Coordinates: | 42.3231°N -75.3116°W[1] |
| Mouth Elevation: | 981feet |
Martin Brook is a river in Otsego County, New York. It converges with the Susquehanna River in Unadilla.