Peters Brook is a tributary of Stony Brook in Mercer and Hunterdon counties, New Jersey in the United States.
The Peters Brook starts at , near the intersection of Rock Road East and CR-601 (Mt Airy-Harbourton Road). It flows northeast, crossing Rock Road East and CR-579 (Linvale-Harbourton Road). It flows past the Pine Creek Golf Course before crossing Route 31 and draining into the Stony Brook at .