The invention provides a shifting driver and a variable-speed device. The shifting driver comprises a drive mechanism and a connector driven by the drive mechanism, wherein the connector is provided with a first end and a second end; the first end is connected with the drive mechanism through a universal joint; and the connector can rotate around the first end as a pivot point, so that the connector has the freedom degree of driving the second end to carry out circumference force nutation in the axial direction vertical to the connector. The shifting driver and the variable-speed device are relatively easy to connect.