A magnetic head includes a magnetic head slider; and a laser diode that is positioned on a surface of a side opposite to a substrate of the magnetic head slider and that generates laser light; the magnetic head slider including: a core through which the laser light emitted from the laser diode propagates as propagating light; a cladding that covers the core and that has a refractive index that is smaller than that of the core; a near field light generating means that generates near field light from the propagating light on an air bearing surface; and a main pole for recording that is disposed adjacent to the near field light generating means and of which an edge part is positioned on the air bearing surface. The core includes a reflection layer and a seed layer, the reflection layer has a refractive index smaller than that of the core, and has a reflection surface on which laser light emitted from the laser diode reflects so as to enter the core as the propagating light, and the seed layer is positioned on a back surface of the reflection surface of the reflection layer and suppresses plasmon generation on the reflection surface.