An antenna driving apparatus includes: a direct current power source supplying direct current power to a human detecting IC detecting contact to a human detecting area by a user, the power source outputting a power source voltage to a first connecting line connected to a power source terminal of the IC and outputting a reference potential to a second connecting line connected to a GND terminal of the IC; an antenna driving circuit driving an antenna transmitting a signal to a portable device, the antenna driving circuit outputting a first antenna drive signal to the first connecting line and outputting an antenna drive signal; and a control unit performing switching control of the power source voltage and the antenna drive signal to be output to the first and second connecting lines and switching control of the antenna driving circuit.