A warning system warns a driver of a vehicle that a vehicle location in a record of previously detected drive operation that indicates a violation of a safety standard and a current position of the vehicle are determined to be within a predetermined distance from each other based on repeated detections of a current vehicle position by a detector and a detection of the drive operation that indicates the violation of the safety standard transmitted through an interface from a drive recorder. In this manner, the warning system for warning the driver lightens a process load of a unit that performs a position detection process and a unit that performs a record keeping process.