The influence regularity of the parameters of the extrusion cooking system for wheat used as beer adjunct on indexes observed was studied by experiments. These parameters include the diameter of nozzle, barrel temperature, moisture content percentage of the wheat, screw speed, and the distance from the internal surface of die plate to the end surface of the end of the whole screw. The indexes observed include the filtration speed of wort, the recoverable ratio of wort extract and iodine value of wort. The research results indicate the extruded wheat may be used as beer adjunct. Meanwhile the recoverable ratio of wort extract for extruded wheat is 74.38% which is more than that of the traditional non-extruded wheat, when the diameter of nozzle is 12 mm, barrel temperature is 60℃, moisture content percentage of wheat is 20%, screw speed is 200 r/min, and the distance from the internal surface of die plate to the end surface of the end of the whole screw is 15 mm. 