Vehicle-state obtaining apparatus

A vehicle-state obtaining apparatus having (a) a sensing device (10-16) including at least one sensor (50) detecting a state of a vehicle and operable to transmit, by radio communication, sensor information including the vehicle state detected by the sensor, and (b) an information processing device (38) operable to receive the sensor information and obtain the vehicle state on the basis of the received sensor information, wherein the information processing device obtains the vehicle state when it is recognized by one-way or two-way communication of key information between the information processing device and the sensing device that these two devices correspond to each other.