To provide a method of processing a wafer, capable of reducing chippings caused in an annular projecting part, and efficiently discharging a treatment liquid such as an etchant or a resist liquid to the outside of the wafer.

The method of processing a wafer includes: a holding step of holding a front surface side of the wafer with a protective member arranged thereon by using a holding means including a holding surface and a rotary shaft vertical to the holding surface; and a grinding step of bringing a grinding wheel into contact with the back surface of the wafer held by the holding means rotated and driven while rotating the grinding wheel to grind the back surface of the wafer corresponding to a device region of the wafer, to form a circular recessed part on the back surface, and of forming an annular projecting part surrounding the circular recessed part, wherein, in the grinding step, the grinding wheel is fed in a direction coming close to the wafer by relatively moving the grinding wheel and the holding means, and is moved in the central direction of the wafer at the same time, whereby a tapered surface tilting from the upper surface inner peripheral side of the annular projecting part toward the wafer center direction of the circular recessed part is formed.