A magnetoresistive head has a substrate (1) and, on the substrate, a magnetoresistive film (40) for converting a magnetic signal into an electric signal by using magnetoresistance effects and a pair of electrodes (60) for causing a signal detection current to flow through the magnetoresistive film. A pair of first domain wall suppressing layers (30) are arranged at opposite end portions of the magnetoresistive film, respectively, to apply a longitudinal magnetic bias to the magnetoresistive film. A second domain wall suppressing layer (45) is also provided for applying a longitudinal magnetic bias, which is weaker compared with the longitudinal magnetic bias applied by the first domain wall suppressing layers, to the magnetoresistive film (40).