Intake system of internal combustion engine

An internal combustion engine includes an intake port (5) leading to an engine cylinder (2). The intake port is divided into first and second passage section by a partition (11) extending in the intake port in a longitudinal direction of the intake port. A gas motion control valve (31) is arranged to open and close an upstream end of the second passage section (5B). A connection passage (12) connects an upstream end portion of the second passage section (5B) to the first passage section (5A). A fuel injector (41) is directed to inject fuel toward a valve opening of the intake valve through a space (5C) on the downstream side of the downstream end of the partition (11).