an injection stretch - blow molding machine for producing hollow articles such as bottles by simultaneously performing the formation of a parison by injection molding and sharping of the parison by stretch - blow molding . the machine has an injection mold constituted by a male mold part and a female mold part and a stretch - blow mold constituted by a male mold part and a female mold part . the machine further has four neck molds capable of opening and closing to release and clamp the neck of the parison and arranged on a rotary body at a 90 ° interval . the rotary body is rotatable to bring the neck molds successively through an injection position , heating position , blow position and a discharge position which are arranged at a 90 ° interval . as the rotary body makes the 90 ° intermittent rotation , the parison formed by injection in the injection position is brought by the neck mold to the heating position , and the preceding parison heated in the heating position is conveyed by another neck mold to the blow position to be finished by stretch - blow molding . at the same time , the finished article is conveyed by still another neck mold to the discharge position where the neck mold is opened to release the finished article .