PURPOSE: To make the cutting of unnecessary part after molding unnecessary and, in addition, make it possible to arbitrarily change the shape of parison, when necessary, by a method wherein parison is arranged in a mold and stretched by air blown through a blow pipe therein so as to be formed in the predetermined shape.

CONSTITUTION: Parison 18 is arranged to the mouth part 12 of a mold 10. And, a blow pin 14, on the outer peripheral part of which a press ring 16 is provided, is lowered, resulting in fixing the mouth part of the parison against the stepped part 13 of the mouth part 12 of the mold 10 by pressure with the press ring 16 of the blow pin 14. Thus, the mouth part of the parison 18 is held down by the upper end side of the mouth part 13 of the mold 10. Under the state just mentioned above, by supplying air through the center hole 15 of the blow pin 14 in the parison 18, the parison 18 is fixed to the inner peripheral surface of a cavity by pressure. Thus, a bottle-like container 19 is formed by blow molding.