Abstract: An intake system for an engine is disclosed in which an inlet passageway for one cylinder includes a common inlet passageway and first and second branch inlet passages having a branch portion at a downstream side of the common inlet passageway, said first branch inlet passage communicating with a first inlet port and said second branch inlet passage communicating with a second inlet port; said first inlet port having an opening for the cylinder and being designed to allow air to be admitted into the cylinder in a direction in which the air swirls therein, and said second inlet port having an opening therefor and being designed to cause air to be admitted thereinto in a direction it disturbs formation of such swirls; and said inlet passageway being provided at its inner wall portion with a wall member for deflecting air admitted from the common inlet passageway toward the first branch inlet passage.