A processing probe capable of repairing a mask-pattern without any damage by preventing electric discharge between the mask patterns, which is caused by electrostatic electrification due to friction between a probe and a mask glass substrate, in repairing a black defect (a convex defect) of a photo-mask with the probe microscope technique is provided. A probe used for mechanically scratching a defective portion is arranged to have conductively. This allows static electricity due to friction in processing to be released from the probe, a cantilever and a cantilever holding member to a square body of an apparatus to prevent electrostatic electrification of a mask glass substrate, and thereby, to prevent electric discharge between mask patterns, so that the mask pattern can be repaired without any damage.