To provide a method for estimating and regulating the current offset in an AC motor for reducing a torque ripple by reducing an offset error.

The method for regulating the current offset in the AC motor comprises the steps of integrating a current command value of the multiplied value of a torque command in constant speed control, by a value corresponding to an electric angle by an integrator 10 at each sampling period of a plurality of periods at the electric angel under the control of the AC motor; estimating the offset of a current detecting system with the value obtained by dividing by sampling times (n) by a divider 11 as an offset value; and subtracting the estimated offset value from the current detected value by a subtracter 13 or adding it to the current command value by an adder, thereby regulating the current offset.