The present invention provides a knife sharpening plate and a knife sharpener using same. The knife sharpener comprises: knife sharpening plates each having four edges having an equal length and both ends provided with protrusions or recesses for fixation. The knife sharpener comprises the knife sharpening plates, knife sharpening plate fixing devices, and a knife sharpening stand. The knife sharpening stand is provided with knife sharpening plate fixing grooves directly or by means of knife sharpening plate holders. The knife sharpening plates are detachably provided in the knife sharpening plate fixing grooves. The knife sharpening plate holders are axially connected to the knife sharpening stand. Two identical knife sharpening plate assemblies are crossly provided on the knife sharpening stand in an approximate "X" shape, so as to form a "V"-shaped knife sharpening edge. Handheld portions and the knife sharpening plate assemblies on the knife sharpening stand are respectively axially symmetric along a same central axis. The beneficial effects of the present invention are that: the knife sharpening plates are easy to detach and replace; the four edges can all be used for knife sharpening, such that the utilization rate of the knife sharpening plates is improved; the symmetric structure can implement knife sharpening on both sides; the knife sharpening plate assemblies are elastically connected such that a knife sharpening angle can be changed to make a knife edge smooth.