To provide a vehicle antenna device in which communication can be continued with a simple mechanism even when a part of an antenna is broken.

The present invention relates to a vehicle antenna system comprising a vehicle-outside antenna element 20 and a vehicle-inside antenna element 30 which are partitioned by a roof panel 2 that is the outer panel of a vehicle 1, wherein phases of high frequency signals input from the feeding point A of the vehicle-outside antenna element 20 and the feeding point B of the vehicle-inside antenna element 30 through a coaxial cable 50 by a feeding unit 10 are inverted to each other by a phase inverting means 40 and input directions thereof are made approximately opposite to each other.