PROBLEM TO BE SOLVED: To provide a porous object that prevents a pore from being closed and being changed in shape when a notch recess reaching the pore is formed on an outer peripheral surface of the porous object having the pore, and to provide a processing method thereof.SOLUTION: A grinder 8 or the like is used to form the notch recess 3 on the outer peripheral surface 1a of the porous object 1 having the pore 2a, and thereby an opening 4 is formed where part of the pore 2a is exposed. When the notch recess 3 is formed, an entrance inhibition material 7 is introduced to the pore 2a for preventing foreign matters from entering the pore 2a from the opening 4. The entrance inhibition material 7 causes cutting scraps to be inhibited from entering the pore 2a from the opening 4, and clogging of the pore 2a is therefore prevented.
