The present invention provides a giant magneto-resistive effect device (CPP-GMR device) having a CPP (current perpendicular to plane) structure comprising a spacer layer, and a fixed magnetization layer and a free layer stacked one upon another with the spacer layer interposed between them, with a sense current applied in a stacking direction. The free layer functions such that the direction of magnetization changes depending on an external magnetic field. The spacer layer comprises a first nonmagnetic metal layer and a second nonmagnetic metal layer, each made of a nonmagnetic metal material, and a semiconductor layer formed between the first and the second nonmagnetic metal layer. The semiconductor layer is an n-type oxide semiconductor. When the first and second nonmagnetic metal layers are formed in order, the first nonmagnetic metal layer is formed prior to the second nonmagnetic metal layer, and an anti-oxidizing layer is formed between the first and the semiconductor layer. Theanti-oxidizing layer is formed of a material incapable of producing a Schottky barrier upon joining to the semiconductor layer. It is thus possible to achieve very favorable advantages of obtaining high MR performance without increasing the head noise, and holding back variations of device's area resistivity (AR), thereby making much more improvements in the reliability of film characteristics.