The present invention is to provide a computer mouse having a windable output wire including a housing, a windable wire receiving device retractably mounted in the housing, and an output wire having a first end connected to the wire receiving device and a second end connected to an output plug that is inserted into a main frame of a computer. The output wire is wound around the fixing shaft center, thereby forming an inner circle structure of the output wire, and is wound around a mobile shaft center, thereby forming an outer circle structure of the output wire. The inner circle structure of the output wire and the outer circle structure of the output wire are along two opposite directions, thereby previously leaving a wire winding space, reducing the volume of the housing, and saving the cost of fabrication.