To provide a composite member capable of showing excellent wear resistance and strength even in the case of relatively large size, capable of attaining high friction coefficient, and most suitably used as a stock for brake rotor in particular and a preform capable of manufacturing such a composite member and also to provide a method for manufacturing them relatively easily.

At the time of manufacturing a porous preform used for the manufacture of a composite member, a raw material for preform is dispersed in a dispersion medium and, in a state where a burnable foamed body having continuous bubbles is impregnated with the whole or a part of slurry from which a part of the dispersion medium is or is not sucked to be discharged, the dispersion medium is sucked and discharged from the slurry. Then heating is applied to the above burnable foamed body to burn the body. Successively, the above raw material for preform is sintered. By this method, the part where the burnable foamed body is burned can be used as an easily infiltratable passage for molten light alloy.