An antenna system loaded in a vehicle according to the present invention includes a first antenna system to perform beamforming by a plurality of first communication antenna elements disposed to transmit and receive a first signal according to a first communication system, and a second antenna system to perform a Multi Input Multi Output (MIMO) by a plurality of second communication antenna elements disposed to transmit and receive a second signal according to a second communication system, whereby a plurality of communication services can be provided through a flat vehicle antenna having beamforming array antennas capable of providing next generation communication services and MIMO antennas capable of providing existing mobile communication services.