The mirror-like grinding of brittle materials is required in many precision engineering areas. Ductile-mode grinding, a new grinding technology for brittle materials, is considered as a solution of this difficult-to-cut materials grinding. It is known that the fracture mechanism of brittle materials changes to plastic deformation when extremely small depths of grinding or removal rates are employed. In this paper, ductile-mode grinding experiments has been performed using a micro-positioning grinding table that does not require a position sensor, but uses piezoelectric voltage feedback. With hysteresis-considering reference input, it has a sub-micrometer order of displacement resolution. It is established that the characteristics of the ground surfaces change to those associated with plastic deformation for small depths of grinding.