The victim flagged down a police officer after the truck's passenger-side mirror struck her on Harristown Road, near the intersection of Berkeley Place, and broke off just after 2 p.m., Police Chief Dean Ackermann said.
She described the truck as a black utility-type vehicle commonly used for construction or landscaping.
It was last seen headed east on Harristown Road towards Ackerman Avenue, the chief said.
The bicyclist wasn't seriously injured, Ackermann said.
Anyone who may have witnessed the crash or has information that could help identify the vehicle or driver is asked to contact Glen Rock police: (201) 652-3800.
Click here to follow Daily Voice Cresskill-Closter and receive free news updates.