A valve operating control device for an internal combustion engine having a valve operating mode changing mechanism for switching the opening/closing operation of an intake or exhaust valve between a low-speed operation mode corresponding to a low-speed operation of the engine and a high-speed operation mode corresponding to a high-speed operation of the engine. A control device controls the operation of the valve operation mode changing mechanism according to the rotational speed of the engine for shifting the valve operation mode changing mechanism from the high-speed mode to the low-speed mode where the output torque of the engine is the same in the low- and high-speed operation modes of the valve operation mode changing mechanism and for shifting the valve operation mode changing mechanism from the low-speed operation mode to the high-speed operation mode at a second rotational speed that is higher than the first rotational speed.