An apparatus for correcting offset of current sensors (CS), wherein at least two of three-phase AC currents output from an inverter have their respective current sensors (CS), the apparatus comprising: the inverter configured to convert a DC power into the three-phase AC currents to supply the three-phase AC currents to an electric motor; a current detector comprising the current sensors for sensing current output from the inverter , the apparatus being characterized by : a filter configured to transform the current sensed by the current detector into d-q axis current and to filter the transformed d-axis or q-axis current to extract a high frequency component therefrom; an RMS, or root mean square, calculator configured to convert the high frequency component extracted from the filter into an effective, or RMS, value; and a controller configured to, if the effective, or RMS, value of the d-axis or q-axis current transformed by the RMS calculator is larger than a preset reference, obtain a DC offset corresponding to the smallest one of the effective, or RMS, values of the d-axis or q-axis current while the electric motor is being driven, and correct a present value of the DC offset of each of the current sensors by replacing the present value with the obtained DC offset, wherein the controller obtains the DC offset corresponding to the smallest one of the effective, or RMS, values of the d-axis or q-axis current by repeatedly increasing or decreasing the present value of the DC offset of each of the current sensors (CS) by a certain amount until the effective, or RMS, values of the d-axis or q-axis current decrease and then increase. the inverter configured to convert a DC power into the three-phase AC currents to supply the three-phase AC currents to an electric motor; a current detector comprising the current sensors for sensing current output from the inverter , the apparatus being characterized by : a filter configured to transform the current sensed by the current detector into d-q axis current and to filter the transformed d-axis or q-axis current to extract a high frequency component therefrom; an RMS, or root mean square, calculator configured to convert the high frequency component extracted from the filter into an effective, or RMS, value; and a controller configured to, if the effective, or RMS, value of the d-axis or q-axis current transformed by the RMS calculator is larger than a preset reference, obtain a DC offset corresponding to the smallest one of the effective, or RMS, values of the d-axis or q-axis current while the electric motor is being driven, and correct a present value of the DC offset of each of the current sensors by replacing the present value with the obtained DC offset, a filter configured to transform the current sensed by the current detector into d-q axis current and to filter the transformed d-axis or q-axis current to extract a high frequency component therefrom; an RMS, or root mean square, calculator configured to convert the high frequency component extracted from the filter into an effective, or RMS, value; and a controller configured to, if the effective, or RMS, value of the d-axis or q-axis current transformed by the RMS calculator is larger than a preset reference, obtain a DC offset corresponding to the smallest one of the effective, or RMS, values of the d-axis or q-axis current while the electric motor is being driven, and correct a present value of the DC offset of each of the current sensors by replacing the present value with the obtained DC offset, wherein the controller obtains the DC offset corresponding to the smallest one of the effective, or RMS, values of the d-axis or q-axis current by repeatedly increasing or decreasing the present value of the DC offset of each of the current sensors (CS) by a certain amount until the effective, or RMS, values of the d-axis or q-axis current decrease and then increase. <EOS>