Disclosed is an antenna system, including: an antenna which can switch directivity thereof when receiving an analog television broadcasting signal; a switching section to switch the directivity of the antenna; a measurement section to measure radio wave quality of the analog television broadcasting signal received by the antenna by analyzing the analog television broadcasting signal when the directivity of the antenna is switched by the switching section; a storage section to store data of radio wave quality in different directions measured by the measurement section for each channel; and a control section to control the switching section to switch the directivity of the antenna to one direction having a highest radio wave quality among the different directions corresponding to a desired channel when the desired channel is designated.