| Crystal Brook | |
| Pushpin Map: | New York |
| Pushpin Map Caption: | Location of the mouth of Crystal Brook |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Subdivision Type2: | State |
| Subdivision Name2: | New York |
| Subdivision Type4: | County |
| Subdivision Name4: | Delaware |
| Source1 Coordinates: | 42.2753°N -75.0731°W |
| Mouth: | East Brook |
| Mouth Coordinates: | 42.2618°N -75.051°W[1] |
| Mouth Elevation: | 1647feet |
Crystal Brook flows into the East Brook by Mundale, New York.