The invention discloses an anti-noise structure of an electronic control unit of an engine; an electronic control unit which can control the operation of a jetting system of an engine is arranged on a throttle valve and at least provided with a coupling port, part of an air inletting bypass of the engine and a control valve which controls the breakover and closing of the air inletting bypass of the engine; an anti-noise component is arranged at the position of the upstream of the control valve of the air inletting bypass of the engine and at least provided with a through hole; therefore, the setting of the anti-noise component can effectively reduce the passing-out amount of the noise which is generated by the control valve and further can reduce the noise amount of the electronic controlunit.