A current detection method for a current detection device including magnetism detection elements that detect magnetic flux density and output a voltage signal corresponding to the magnetic flux density is provided. The method includes acquiring measured value data that is obtained as a result of providing magnetic flux density in a detectable range of the magnetism detection elements that indicates the relationship between the magnetic flux density and an output voltage signal from the current detection device. Next, computational processing is performed so as to fit the acquired measured value data to a formula that includes plural factors and indicates the output voltage of the magnetism detection elements, thereby calculating the plural factors, and correcting the output voltage signal from the magnetism detection elements in accordance with the calculated factors so as to be approximately linear with respect to the magnetic flux density. Finally, a corrected voltage signal obtained by the correction is outputted.