The present invention provides a thin film magnetic head capable of suppressing unintentional wiring to a neighboring track and preventing information recorded on a recording medium from being erased. A main magnetic pole layer is constructed so that height of a widened end surface in a lower main magnetic pole layer specifying a wide portion is smaller than height of an exposed surface in an upper main magnetic pole layer (front end portion) specifying a uniform width portion. Since the area of the widened end surface is narrowed with respect to the area of the exposed surface, even if an amount of magnetic flux flowing in the lower main magnetic pole layer increases at the time of recording information, as compared with the case where the height of the widened end surface is equal to the height of the exposed surface, unintentional emission of the magnetic flux flowing in the lower main magnetic pole layer from the widened end surface not via the upper main magnetic pole layer (front end portion) toward the recording medium is suppressed.