The invention is suitable for the intelligent traffic field and provides a license plate number acquisition method. The method comprises steps that a vehicle driving-in signal emitted by a detector ona parking stall is received, and the vehicle driving-in signal contains a unique identifier of the detector; according to the unique identifier of the detector, a corresponding parking stall identifier is acquired; license plate numbers acquired by multiple types of license plate number acquisition approaches are received; when the license plate numbers acquired through any two types of license plate number acquisition approaches are consistent, the corresponding relationship between the acquired license plate numbers and the parking stall identifier is established. The method is advantaged in that a problem of greatly low work efficiency of parking vehicle information management caused by incapability of confirming the specific parking stall parking information because of incapability ofaccurately acquiring the license plate numbers existing in a traditional license plate number management function is solved.