The invention discloses a data processing method and device in a vehicle networking system, and a storage medium. The data processing method in a vehicle networking system includes the steps: determining the current traffic flow information according to a traffic flow data packet acquired at the current time; and determining validity of the acquired traffic flow data packet according to the current traffic flow information and the pre-stored current traffic permission information. The method, the device and the storage medium of the present invention determine the current traffic flow information by using the traffic flow data packet acquired at the current time, and determine the validity of the acquired traffic flow data packet by using the current traffic flow information and the current traffic permission information, so that, in the process of collecting the traffic flow information of the current road section in the sub-network of vehicle networking, the data validity guarantee is provided for the entire vehicle networking, and the system data abnormality caused by malicious attacks is avoided, thereby avoiding harm to personal safety.