A composite valve comprising: a piston type first valve body; a valve shaft provided with a needle type second valve body; an elevation driving means moving said valve shaft up and down a pilot valve body driven so as to be opened and closed by utilizing the elevating motion of said valve shaft; a valve main body provided with an inflow port and an outflow port; the composite valve being structured such that between said inflow port and the outflow port in said valve main body, there are provided a fitting and inserting chamber to which said first valve body is slidably fitted and inserted, and which is comparted into a back pressure chamber and a first valve chamber by said first valve body, a first valve port which is open to said first valve chamber, a second valve chamber in which said pilot valve body and the second valve body are arranged so as to be movable up and down, a second valve port which communicates said inflow port or the first valve chamber with said second valve chamber, and a pilot passage which is open at its upper end to a bottom surface of said second valve chamber so as to communicate said back pressure chamber with said second valve chamber, and the composite valve being structured such that in the case that a lift amount of said second valve body is equal to or less than a predetermined amount (Tc), said pilot passage is closed by said pilot valve body, and said first valve port is closed by said first valve body, thereby taking a small flow rate control state in which a flow rate is controlled in correspondence to the lift amount of the second valve body, and in the case that the lift amount of said second valve body goes beyond said predetermined amount (Tc), said pilot valve body is moved up in conjunction with the upward movement of said valve shaft so as to open said pilot passage, thereby taking a large flow rate control state in which said first valve body opens said first valve port on the basis of this motion, characterized in that said pilot valve body comprises: a valve body member; and a valve body pressing member which is energized downward by a spring member so as to position said valve body member close to or away from an opening edge portion of said pilot passage, and is pulled up against an energizing force of said spring member by a catch portion provided in said valve shaft, if the lift amount of said second valve body is increased further from said predetermined amount (Tc). a piston type first valve body; a valve shaft provided with a needle type second valve body; an elevation driving means moving said valve shaft up and down a pilot valve body driven so as to be opened and closed by utilizing the elevating motion of said valve shaft; a valve main body provided with an inflow port and an outflow port; the composite valve being structured such that between said inflow port and the outflow port in said valve main body, there are provided a fitting and inserting chamber to which said first valve body is slidably fitted and inserted, and which is comparted into a back pressure chamber and a first valve chamber by said first valve body, a first valve port which is open to said first valve chamber, a second valve chamber in which said pilot valve body and the second valve body are arranged so as to be movable up and down, a second valve port which communicates said inflow port or the first valve chamber with said second valve chamber, and a pilot passage which is open at its upper end to a bottom surface of said second valve chamber so as to communicate said back pressure chamber with said second valve chamber, and the composite valve being structured such that in the case that a lift amount of said second valve body is equal to or less than a predetermined amount (Tc), said pilot passage is closed by said pilot valve body, and said first valve port is closed by said first valve body, thereby taking a small flow rate control state in which a flow rate is controlled in correspondence to the lift amount of the second valve body, and in the case that the lift amount of said second valve body goes beyond said predetermined amount (Tc), said pilot valve body is moved up in conjunction with the upward movement of said valve shaft so as to open said pilot passage, thereby taking a large flow rate control state in which said first valve body opens said first valve port on the basis of this motion, characterized in that said pilot valve body comprises: a valve body member; and a valve body pressing member which is energized downward by a spring member so as to position said valve body member close to or away from an opening edge portion of said pilot passage, and is pulled up against an energizing force of said spring member by a catch portion provided in said valve shaft, if the lift amount of said second valve body is increased further from said predetermined amount (Tc). a valve body member; and a valve body pressing member which is energized downward by a spring member so as to position said valve body member close to or away from an opening edge portion of said pilot passage, and is pulled up against an energizing force of said spring member by a catch portion provided in said valve shaft, if the lift amount of said second valve body is increased further from said predetermined amount (Tc).