An antenna system for vehicles includes a first antenna attached in a vicinity of a windshield of a vehicle; and a second antenna attached in a vicinity of a rear glass of the vehicle, wherein the first antenna and the second antenna are configured to transmit and receive an electromagnetic wave in a predetermined frequency band F, and wherein defining a region A and a region B with respect to a vehicle center axis extending in a traveling direction of the vehicle, so as to bisect a vehicle width of the vehicle from a viewpoint in a direction normal to a horizontal plane, the first antenna is arranged in the region A, and the second antenna is arranged in the region B.