A perpendicular magnetic recording medium having a soft magnetic backing
layer in which amount of cobalt elution is suppressed without imposing
restraint on the construction of the protective layer is disclosed. The
perpendicular magnetic recording medium of the invention comprises at
least a soft magnetic backing layer, a magnetic recording layer, and a
protective layer sequentially laminated on a nonmagnetic substrate, the
soft magnetic backing layer containing iron and cobalt, and further
containing at least two elements selected from Si, Ni, Ta, Nb, Zr, Ti,
Cr, Mo, and B, and the surface roughness of the soft magnetic backing
layer being in a range of 0.2 nm to 0.8 nm in center line average
roughness. The iron concentration in the soft magnetic backing layer
preferably is in the range of 40 at % to 85 at %, the cobalt
concentration preferably is in a range of 10 at % to 45 at %, and the
total concentration of Si, Ni, Ta, Nb, Zr, Ti, Cr, Mo, and B is in a
range of 20 at % to 50 at %.