PURPOSE: To suppress the generation of a sound and vibration through the change of the flow of fluid in an fluid outlet chamber and pressure distribution and to improve quality of a gas proportional valve having wide control capacity through a simple constitution by disposing a member for noise prevention in the fluid outlet chamber of a gas proportional valve.

CONSTITUTION: A gas proportional valve comprises a valve body 1 being a housing; a valve body 5 contained therein; and the drive part of the valve body 5. When, by applying a current on the electromagnetic coil 8 of a drive part, a plunger 7 is attracted and the valve body 5 is pressed down, the valve body 5 is parted from a valve seat 4, fluid flows through a fluid inlet chamber 2 to a fluid outlet chamber 3. In this case, fluid between the valve seat 4 and the valve body 5 generates a sound. However, in such a way that the flow of fluid is collided with a member 18 for noise prevention, the flow of fluid in a fluid outlet chamber 3 and pressure distribution of a flow are changed, the generation of a sound and vibration is suppressed.