A process for manufacturing a lithographic printing plate support made of aluminum or an aluminum alloy, in which the surface of the support is mechanically roughened by graining it with a brush comprising bristles which have a bending elastic modulus of 10,000 to 40,000 kg/cm.sup.2 and a nerve of 500 g or less per bristle, whereby generation of defective products due to defects such as scratching which aluminum itself has can be prevented and a lithographic printing plate support having scumming reduction even on squeezing water out can be provided.