<p>An integrated gas valve (1) formed so that a turbulent flow portion is not produced in carrying gas and that process gas flowed in the carrying gas is not diffused, comprising first flow passages (26) in which open/close valves (30) allowing valve elements (33) to be brought into contact with and separated from valve seats (34) by an actuator (31) to communicate and cut out valve holes (35) with and from valve chambers (36) are formed through a valve body (12) so as to be branched midway from the valve holes (35) and a second flow passage (29) formed in the valve body (12) to communicate input ports to the valve chambers, wherein the plurality of open/close valves are continuously arranged with each other in one row to form a main flow passage (23) in which the first flow passages (26) are directly connected to each other or connected in series through a connection flow passage (27) and the second flow passages (39) of the open/close valves are connected to the main flow passage (23) through the valve chambers (36) and the valve holes (35).</p>
