| Clear Brook | |
| Name Other: | Tributary to Nanticoke River |
| Map Size: | 180 |
| Pushpin Map: | Delaware#USA |
| Pushpin Map Size: | 180 |
| Pushpin Map Caption: | Location of Clear Brook mouth |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Subdivision Type2: | State |
| Subdivision Name2: | Delaware |
| Subdivision Type3: | County |
| Subdivision Name3: | Sussex |
| Length: | 8.87miles[1] |
| Discharge1 Location: | Nanticoke River |
| Discharge1 Avg: | 27.29cuft/s at mouth with Nanticoke River[2] |
| Source1: | divide between Clear Brook and Bridgeville Branch of Nanticoke River |
| Source1 Location: | about 1 mile southwest of Bridgeville, Delaware[3] |
| Source1 Coordinates: | 38.7319°N -75.6383°W[4] |
| Source1 Elevation: | 46feet |
| Mouth: | Nanticoke River |
| Mouth Location: | Seaford, Delaware |
| Mouth Coordinates: | 38.6408°N -75.6061°W |
| Mouth Elevation: | 0feet |
| Progression: | Nanticoke River → Chesapeake Bay → Atlantic Ocean |
| River System: | Nanticoke River |
| Tributaries Left: | William H. Newton Ditch |
| Tributaries Right: | Swain and Truitt Ditch Bucks Branch Herring Run |
| Waterbodies: | Hearns Pond Williams Pond |
Clear Brook is a 23.02miles long tributary to the Nanticoke River in Sussex County, Delaware. It joins the Nanticoke at "Williams Pond" in the City of Seaford, Delaware.