A vehicle data processing system is provided which, even if an on-vehicle data processor such as a navigation system or the like is not active, can input the necessary data into the system at an operator's home or the like. A vehicle includes a data processor and an input unit is independently located in the operator's home or other place. Data of destination and the like inputted into the input unit are transmitted to an information center wherein they are stored in a storage unit. When a sensor in the information center senses that the data processor on the vehicle has become active, the input data are transmitted from the input unit to the data processor.