The machine is used to blowing the plastic films by the material of LDPE or HDPE. It had been applied extensively in the productions of foodstuff bags, purchase bags, inner packing bags or the plastic woven sacks & agro-field films. The material of LDPE or HDPE can produce the plastic films on the shape of circular cylinder after been heated, extruded, blown, drawn & winded. The cylinder & screw of the extruder are made by alloy steel of 38CrMoAlA after the treatment of Nitric. The Extruder and drawing parts are controlled by step less speed charge device. Since all the drawing rollers had been treated by the Electroplated with Chromium, so their service lives had been extended much longer. The machine which had been equipped with the single extruder & double dies can blow 2 colors of the plastic film simultaneous. The extruder of the machine with double colors can blow the stripes film with 2 colors.