The present invention provides a method of treatment for imparting conductivity to a surface of a separator-use base member resulting in little distortion and superior conductive performance for a separator-use base member of a solid polymer type fuel cell made of any of a sheet of stainless steel, titanium, or titanium alloy, comprising a step of spray coating and drying on the surface of the separator-use base member a suspension prepared by mixing conductive compound particles 3 of an average particle size of 1 to 10 μm with ethanol or water so as to form a conductive compound particle-coated layer 2, a step of blasting the conductive compound particle-coated layer 2 with blast particles 4 having an average particle size of 50 to 200 μm so as to drive the conductive compound particles 3 in the inside direction of the separator-use base member 3 and anchor them there, and a step of cleaning off conductive compound particles 3 not anchored to the surface of the separator-use base member 1 at that step and impurities.