GRIP GRASPING STATE DETERMINATION DEVICE, DETERMINATION METHOD, AND SYSTEM INCLUDING DETERMINATION DEVICE

A grip grasping state by a driver of a two-wheeled motor vehicle is accurately determined. A grip grasping state determination device according to the present invention has: a grip sensor that is attached to a driving operation handlebar for the two-wheeled motor vehicle and detects vibration of a grip grasped by the driver of the two-wheeled motor vehicle; a storage section that stores a vibration pattern according to a grip grasping state by the driver; and a determination section that determines the grip grasping state by the driver on the basis of the vibration detected by the grip sensor and the vibration pattern.