A lubricating system for a valve operating system includes a valve operating system configured to reciprocate a valve for substantially opening and closing a port connected to a combustion chamber of an engine, and an ejecting device provided with an outlet from which a lubricating liquid is ejected. The valve operating system includes a drive cam, a driven member configured to contact the drive cam, a pivot member which is attached to the driven member and is configured to transmit movement of the driven member to the valve, and a relative position changing device configured to change relative positions of the driven member and the pivot member. The outlet of the ejecting device is oriented to face sliding surfaces of the driven member and the drive cam at least in a period which is a part of one rotation of the drive cam.