An apparatus for matching impedance using Standing Wave Ratio, abbreviated as SWR, information, the apparatus comprising: a directional coupler configured to extract forward power of a transmission signal traveling to be transmitted through an antenna, and reflected power of the transmission signal reflected from the antenna; the apparatus further comprising an impedance matching unit configured to match an impedance of the antenna by varying impedance according to a control signal, wherein the impedance matching unit includes a variable capacitor; a forward power detection unit configured to detect the forward power from an output signal of the directional coupler; a reflected power detection unit configured to detect the reflected power from the output signal of the directional coupler; an SWR operation unit configured to calculate an SWR by using the forward power detected by the forward power detection unit and the reflected power detected by the reflected power detection unit; and an impedance control unit characterised in that said impedance control unit is configured to determine a region of a Smith chart in which an initial total impedance of the impedance matching unit and the antenna is located, by using the SWR calculated by the SWR operation unit, and configured to change the capacitance value of the variable capacitor of the impedance matching unit according to the determined region to thus control the impedance of the antenna to be matched, wherein the Smith chart is divided into first to sixth regions (T1 to T6), and the first region is the inside region of the impedance circle within the inductive region, and the second region is the outside region of the impedance circle and the admittance circle within the inductive region, and the third region is the inside region of the admittance circle within the inductive region, and the fourth region is the inside region of the admittance circle within the capacitive region, and the fifth region is the outside region of the impedance circle and the admittance circle within the capacitive region, and the sixth region is the inside region of the impedance circle within the capacitive region, wherein the impedance circle and the admittance circle passes through a center point of the real axis of the Smith chart, and wherein in the matching of the impedance, the impedance control unit is adapted to control the impedance of the impedance matching unit such that the total impedance of the impedance matching unit and the antenna meets the impedance circle or the admittance circle of a Smith chart and then has desired impedance. a directional coupler configured to extract forward power of a transmission signal traveling to be transmitted through an antenna, and reflected power of the transmission signal reflected from the antenna; the apparatus further comprising an impedance matching unit configured to match an impedance of the antenna by varying impedance according to a control signal, wherein the impedance matching unit includes a variable capacitor; a forward power detection unit configured to detect the forward power from an output signal of the directional coupler; a reflected power detection unit configured to detect the reflected power from the output signal of the directional coupler; an SWR operation unit configured to calculate an SWR by using the forward power detected by the forward power detection unit and the reflected power detected by the reflected power detection unit; and an impedance control unit characterised in that said impedance control unit is configured to determine a region of a Smith chart in which an initial total impedance of the impedance matching unit and the antenna is located, by using the SWR calculated by the SWR operation unit, and configured to change the capacitance value of the variable capacitor of the impedance matching unit according to the determined region to thus control the impedance of the antenna to be matched,