To provide a variable intake device of an in-line fourcylinder internal combustion engine, capable of obtaining high intake air filling efficiency and high output torque in the wide rotational speed range

Ends of four independent intake passages having the approximately equal length and the other ends to be communicated with and connected to respective cylinders are communicated with and connected to a single intake collection chamber. An intake control valve 5 having first to third valve vanes 71 to 73 on a valve shaft 6 is interposed in a communication passage formed on a collecting part of the intake passage so that the valve shaft 6 may extend between mutually adjacent intake passages provided for each cylinder groups having intake strokes not to be continued. Communication ports 111, 112 are respectively formed on the first and second valve vanes 71, 72 by matching the phases in the rotational direction, and a communication port 113 is formed on the third valve vane 73 by deviating the phase from the communication ports 111, 112 in the rotational direction. The intake control valve 5 is switched in three stages according to the rotational speed so that the first to third communication ports 111 to 113 and openings 81 to 84 may coincide or not coincide with each other.