A magnetic head for a magnetic recording/reproducing device to conform to high-density recording, wherein a metal magnetic film with a high saturation flux density is employed and the mechanical strength of the sealing glass for magnetic heads, is improved thereby achieving a high reliability, high performance magnetic head. Also, this is provided a magnetic recording/reproducing device utilizing the magnetic head. Sealing glass for magnetic heads comprising, by oxide conversion, 17.2 to 25 wt % of SiO₂, 1 to 10 wt % of B₂O₃, 58 to 75 wt % of PbO, 0.2 to 7 wt % of at least one of Al₂O₃ and ZnO, and 0.2 to 5 wt % of at least one of Na₂O and K₂O, and a magnetic head and magnetic recording/reproducing device which utilize the sealing glass.