A driving information generating section 20 successively generates as driving information diverse types of information indicative of a driving state of a vehicle. A dangerous driving determining section 31 determines whether dangerous driving is underway on the basis of the driving information generated by the driving information generating section 20. A supplementary information acquiring section 32 acquires state supplementary information manually or automatically upon determination of dangerous driving by the dangerous driving determining section 31, and associates the acquired state supplementary information with the result of the determination of dangerous driving. An information communication section 34 transmits the result of the determination of dangerous driving and the state supplementary information to an information management apparatus 40. The information management apparatus 40 can recognize the state of the case in which dangerous driving is underway based on the state supplementary information, and correctly determine validity of the result of the determination of dangerous driving.