A wafer processing apparatus for pre-alignment and edge exposure of a wafer, comprising: a rotary table, for carrying the wafer; a motion module comprising, from top down, a rotation module, a lifting module and a translation module interconnected to one another, the rotation module being connected at a top thereof to the rotary table and configured to drive the rotary table to rotate together with the wafer, the lifting module being configured to drive the rotation module and the rotary table to move vertically and enabling the wafer to move at least between a first height and a second height, the translation module being configured to drive the lifting module and the rotation module to move horizontally in one dimension along a guide rail; a pre-alignment module, configured to collect positional information of the wafer when the wafer is located at a pre-alignment height; an edge exposure module, configured to perform edge exposure on the wafer, wherein the pre-alignment module and the edge exposure module are positioned at opposing sides of the wafer; a control module, electrically connected to the pre-alignment module, the edge exposure module and the motion module and configured to receive the positional information of the wafer and to control, based on the received information, the motion module to adjust a position of the rotary table so as to accomplish pre-alignment of the wafer, the control module being further configured to control the edge exposure module to accomplish the edge exposure of the wafer; and a positioning table positioned between the first height and the second height, wherein the positioning table allows the rotary table but not the wafer to vertically pass therethrough, and wherein the positioning table is configured to retain the wafer by suction when the wafer is in proximity thereto. a rotary table, for carrying the wafer; a motion module comprising, from top down, a rotation module, a lifting module and a translation module interconnected to one another, the rotation module being connected at a top thereof to the rotary table and configured to drive the rotary table to rotate together with the wafer, the lifting module being configured to drive the rotation module and the rotary table to move vertically and enabling the wafer to move at least between a first height and a second height, the translation module being configured to drive the lifting module and the rotation module to move horizontally in one dimension along a guide rail; a pre-alignment module, configured to collect positional information of the wafer when the wafer is located at a pre-alignment height; an edge exposure module, configured to perform edge exposure on the wafer, wherein the pre-alignment module and the edge exposure module are positioned at opposing sides of the wafer; a control module, electrically connected to the pre-alignment module, the edge exposure module and the motion module and configured to receive the positional information of the wafer and to control, based on the received information, the motion module to adjust a position of the rotary table so as to accomplish pre-alignment of the wafer, the control module being further configured to control the edge exposure module to accomplish the edge exposure of the wafer; and a positioning table positioned between the first height and the second height, wherein the positioning table allows the rotary table but not the wafer to vertically pass therethrough, and wherein the positioning table is configured to retain the wafer by suction when the wafer is in proximity thereto.