PURPOSE: To improve warming-up performance of a catalytic rhodium at the time of cold starting by keeping an intake control valve disposed in one of two air intake passages in the open state during a designated period of time at the time of engine cold starting, and then opening and closing the valve according to the engine load in a variable swirl type air intake device.

CONSTITUTION: An air intake port 7 of an internal combustion engine is divided into a helical passage 11 turned round the open end 7a to a combustion chamber and a straight passage 12 rectilinearly communicating with the open end 7a by a guide vane 10 expanded from the ceiling wall portion downward. An air intake control valve 13 for opening and closing the passage 12 is disposed in the middle of the straight passage 12. In this case, the intake control valve 13 is controlled to be kept in the open state during a designated period of time at the time of cold starting the engine, whereby after cold starting, the temperature of exhaust gas is raised quickly to enhance the warming-up performance of a catalytic converter rhodium. After that, the valve is opened and closed according to the engine load to satisfy various requirements ranging from low load to high load.