Disclosed in the present invention are a vehicle-borne payment method and device, relating to the technical field of vehicle-borne security payment. The method includes: receiving a vehicle-borne payment request sent by a vehicle, the vehicle-borne payment request including vehicle identification information; according to the vehicle identification information, after the vehicle is determined as a registered vehicle, obtaining driving attribute data of the vehicle within the current time period, and a vehicle driving strategy of the vehicle; according to the driving attribute data in the current time period, and the vehicle driving strategy, determining a risk level corresponding to the vehicle-borne payment request; and sending the risk level to a transaction platform so that the transaction platform determines whether to make a payment according to the risk level. The vehicle driving strategy is, after the vehicle applies for registration, formed according to driving attribute data in a preset time period. In an embodiment of the present invention, it is ensured that even if a vehicle is stolen or used by others, the transaction platform determines whether to make the payment according to a risk level, thereby ensuring the security of vehicle-borne payment.