An angle adjustment mechanism, comprising: a first body, having a first positioning structure; a second body, movably coupled to the first body and having a second positioning structure and a sliding slot, wherein the second positioning structure and the first positioning structure are engaged to each other, and the second body is adapted to rotate relative to the first body about an axial direction, so that the second positioning structure moves away from the first positioning structure along a radius direction; and a restoring element, coupled to the second body and adapted to accumulate a restoring force when the second positioning structure moves away from the first positioning structure along the radius direction, wherein the second positioning structure is adapted to approach the first positioning structure along the radius direction via the restoring force after the second body rotates an angle relative to the first body, so as to be reengaged to each other, characterized by a fixing base, having an accommodation space and connected with the first body and the second body, wherein the restoring element is disposed within the accommodation space, wherein the second body is located between the first body and the fixing base, and wherein the fixing base is adapted to rotate relative to the first body about the axial direction and drive the second body to rotate relative to the first body and to move within the accommodation space, so that the restoring element is deformed within the accommodation space for accumulating or releasing the restoring force; and a pivot, disposed between the first body and the second body and passing through the first body, the sliding slot of the second body, and the fixing base along the axial direction, wherein the first body, the second body and the fixing base are pivoted together by the pivot, so that the second body is adapted to rotate relative to the first body about the axial direction via the pivot and move relative to the pivot through the sliding slot. a first body, having a first positioning structure; a second body, movably coupled to the first body and having a second positioning structure and a sliding slot, wherein the second positioning structure and the first positioning structure are engaged to each other, and the second body is adapted to rotate relative to the first body about an axial direction, so that the second positioning structure moves away from the first positioning structure along a radius direction; and a restoring element, coupled to the second body and adapted to accumulate a restoring force when the second positioning structure moves away from the first positioning structure along the radius direction, wherein the second positioning structure is adapted to approach the first positioning structure along the radius direction via the restoring force after the second body rotates an angle relative to the first body, so as to be reengaged to each other, characterized by a fixing base, having an accommodation space and connected with the first body and the second body, wherein the restoring element is disposed within the accommodation space, wherein the second body is located between the first body and the fixing base, and wherein the fixing base is adapted to rotate relative to the first body about the axial direction and drive the second body to rotate relative to the first body and to move within the accommodation space, so that the restoring element is deformed within the accommodation space for accumulating or releasing the restoring force; and a pivot, disposed between the first body and the second body and passing through the first body, the sliding slot of the second body, and the fixing base along the axial direction, wherein the first body, the second body and the fixing base are pivoted together by the pivot, so that the second body is adapted to rotate relative to the first body about the axial direction via the pivot and move relative to the pivot through the sliding slot.