To provide an intake pipe structure of an engine for a small-sized planing boat capable of effectively reducing noise generated from an induction system of an engine and effectively restraining introduction of water into the induction system.

Two intake boxes 5, 8 are arranged to intake pipes 6, 9 of an engine 1. One intake box 5 is arranged on one side of the engine 1 below a draft line of a boat, and the other intake box 8 is arranged on the other side above the draft line. The ends of the intake pipes 6, 9 connected with downstream of intake from the respective boxes 5, 8 are connected with the top of the intake boxes. A throttle valve 7 is installed to one intake pipe 6, and an air suction valve 12 for sucking new charge from the upstream of the throttle valve 7 and transferring it near the outlet of an emission port of the engine is provided. A sound absorbing member is arranged to the air suction valve 12.