Washington Township Officer Heather Castronova was walking back to her squad car after issuing a summons when she was hit around 3:45 a.m. Saturday.
Authorities say she didn't have time to avoid the speeding, dark-colored SUV, which fled from the scene.
Castronova was treated at a hospital for injuries to her head and right arm and later released. She is expected to fully recover, but will likely be out of work indefinitely.
The police union in the Bergen County community is offering a $2,500 reward for information leading to the arrest of the SUV's driver.