| Back Brook | |
| Source1 Coordinates: | 40.4428°N -74.71°W |
| Mouth Coordinates: | 40.4394°N -74.6461°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Progression: | Pike Run, Beden Brook, Millstone River, Raritan River, Atlantic Ocean |
| Mouth Elevation: | 56feet |
| River System: | Raritan River system |
| Tributaries Right: | Branch Back Brook |
Back Brook is a tributary of Pike Run in Somerset County, New Jersey in the United States. It is located on the east side of Sourland Mountain.
Back Brook starts at 40.4428°N -74.71°W,[1] on the edge of Sourland Mountain. It flows eastward, crossing Blawenburg-Belle Mead Road and Sunset Road before running through Schuss Woods and the McAlpin Farm Easement. It then crosses Route 206 and flows through Oxbridge before entering Pike Run at 40.4394°N -74.6461°W.[1]