An impedance matching apparatus is provided. The impedance matching apparatus includes a signal separation unit, an impedance detection unit, and an impedance matching unit. The signal separation unit separates a transmission and reception signal, and selectively passes a desired frequency corresponding to the transmission and reception signal. The impedance detection unit includes a plurality of impedances, and detects first and second electric potentials between the impedances. The impedance matching unit compares the first and second electric potentials detected by the impedance detection unit, and changes a matching factor for one of the impedances included in the impedance detection unit to match the impedances according to the compared result.