| Gulf Brook | |
| Pushpin Map: | USA New York#USA |
| Pushpin Map Caption: | Location of the mouth of Gulf Brook in New York |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Subdivision Type2: | State |
| Subdivision Name2: | New York |
| Subdivision Type3: | County |
| Subdivision Name3: | Delaware |
| Source1 Coordinates: | 42.0592°N -74.8439°W |
| Mouth: | Holliday Brook |
| Mouth Coordinates: | 42.0556°N -74.8699°W[1] |
| Mouth Elevation: | 1457feet |
Gulf Brook is a river in Delaware County in New York. It flows into Holliday Brook east-southeast of Downsville.