A handheld electronic device including a first body, a second body, and a rising mechanism is provided. The second body is stacked under the first body. A side of the second body facing the first body has a depression. The rising mechanism is connected between the first body and the second body. The rising mechanism is slidably coupled to the first body, so that when the first body and the second body are relatively spread, the first body slides relative to the rising mechanism. In addition, when the first body reaches a predetermined position, an end of the first body enters the depression, the rising mechanism drives the first body to rotate relative to the second body, and an upper surface of the first body and an upper surface of the second body form an angle.