The invention discloses a quick-change connector, which comprises a primary connector and a secondary connector, wherein the primary connector is a normally stopped connector which is connected under the action of axial movement of a valve plug (12); the secondary connector can be inserted into the primary connector and push the valve plug (12) to move axially; and one end of the secondary connector is provided with a first connecting part which is connected with a pipeline. The quick-change connector is installed at one time and is not needed to be detached. The secondary connector is connected with an oil filling/draining pipe; and during use, the secondary connector is inserted into the primary connector on a yawing variable pitch gearbox, and the oil is filled or drained easily and rapidly. The primary connector has a one-way non-return form, and cannot be connected under the action of inner oil pressure of the gearbox but can be connected under an external pressure; therefore, the gearbox cannot leak oil, and the oil is filled easily. The invention also discloses a yawing variable pitch gearbox with the quick-change connector.