Vehicle data updating method and vehicle data updating system

Provided is a vehicle data updating method. A PC acquires railway basic data of train operation and converts the form of the railway basic data to obtain a data file, then the data file is written into an on-line programming device, and the on-line programming device updates the data file to a monitoring record plug-in. The monitoring record plug-in is located in a train operation monitoring device, and the monitoring record plug-in receives the sent data file and transmits the data file to the train operation monitoring device. By means of the technical scheme, the monitoring record plug-in is arranged in the train monitoring device, the on-line programming device is adopted to serve as an intermedium to update the vehicle data of a train to the monitoring record plug-in, thus erasure of an EPROM is avoided, and update of the vehicle data can be simply and conveniently achieved.