Actuator of link mechanism for internal combustion engine

Provided is an actuator of a link mechanism for an internal combustion engine, in which a reduction gear can be sufficiently lubricated. The actuator is provided with an oil channel that is formed ina control shaft for changing the orientation of a control link and that supplies lubricating oil to the reduction gear, and an opening that opens toward the reduction gear in one end side which is theside near the reduction gear, and that is communicated with the oil channel in the other end side, the inside diameter of the one end side of the opening being greater than the outside diameter of one end side of the oil channel. 本发明提供种内燃机用连杆机构的促动器，其能够充分地进行减速机的润滑。具有：油路，其形成于改变控制连杆的姿势的控制轴且向减速机供给润滑油；开口部，其减速机侧的端侧向减速机开口且另端侧与油路连通；使开口部的端侧的内径大于油路的端侧的外径。