A central active area includes a MR film, a nonmagnetic spacer film and a soft magnetic film with the MR film constituting the lowermost layer on top of a supporting body, the nonmagnetic spacer film laminated on top of the MR film and the soft magnetic film laminated on top of the nonmagnetic spacer film to provide a lateral bias field to the MR film. A magnetic transducer and a thin film magnetic head with which the main peak width in the off track characteristics can be increased and, consequently, the margin can be increased are provided.