A hydroplaning determination device that determines occurrence of a hydroplaning phenomenon in a vehicle includes a tire mount sensor including a vibration detection unit, a signal process unit and a transmission unit, and a vehicle body system including a receiver, a condition determination unit and a hydroplaning determination unit. The vibration detection unit is attached to a rear surface of a tire provided in a vehicle and outputs a detection signal according to a magnitude of vibration of the tire. The signal process unit generates a vibration data based on the detection signal. The hydroplaning determination unit determines, based on the vibration data, whether a hydroplaning phenomenon has occurred when the condition determination unit determines that a road surface condition is a wet condition in which a water film exists between the tire and a road surface.