A resonator has a volume chamber, which is communicated with a surge tank through a communication passage. A primary intake passage communicates between a cylinder of an internal combustion engine and the surge tank. A secondary intake passage communicates between the surge tank and one of the cylinder and the primary intake passage. A passage length of the secondary intake passage is shorter than a passage length of the primary intake passage. A variable intake valve is fixed to a shaft. The variable intake valve opens and closes the secondary intake passage. A resonator valve is fixed to the shaft. The resonator valve opens and closes the communication passage. A drive device rotates the shaft to drive the variable intake valve and the resonator valve.