The present invention makes it possible to favorably change valve-opening characteristics of a valve using a simplified configuration without leading to an increase in the number of components and also without causing an increase of friction due to sliding, in a valve operating apparatus for an internal combustion engine in which the valve-opening characteristics of the valve are variable. A changeover mechanism for switching the connection/disconnection of rocker arms disposed between cams and a valve is provided. When a slide pin reaches a displacement end in the retreating direction of changeover pin, the biasing force of a return spring acting on changeover pins is received by an engaging part between a notch part provided in the slide pin and a lock pin in a state separated from a camshaft.