Provided is a control apparatus, which can successfully suppress that deterioration of combustion is caused in response to inflow of a large amount of blow-by gas to cylinders at the time of a valve return from a valve stop state in an internal combustion engine including a positive crankcase ventilation system and a variable valve operating mechanism that is capable of stopping at least one valve of an intake valve and exhaust valve in a closed state. A valve stop control is performed which stops the intake valve and exhaust valve in a closed state when a fuel cut of the internal combustion engine is executed. A deviation amount ΔA/F between a predetermined target air fuel ratio and an actual air fuel ratio detected by an A/F sensor at the time of a valve return is obtained. A correction is performed to decrease a fuel injection amount by a fuel amount equivalent to the deviation amount ΔA/F at the time of the subsequent valve returns.