PURPOSE: To mold a lightweight bent container by using necessary min. amt. of a resin so as to not only to reduce the deflection of a parison but also to stably obtain constant wall thickness.

CONSTITUTION: A container having a bent part formed to a part thereof is molded by a blow molding method using a mold divided into split molds. A parison 2 is suspended in the cavity 22 having the outer shape of the container to be molded and having a mouth part 26 formed thereto along a vertical direction to be downward inclined from a bent position formed between the split molds at the position of the mouth part 26 and the lower part of the parison is inserted in the gap between the front and rear supports 38, 40 provided to a moving member 36 at the lower position of the mouth part and, after the parison is arranged in the cavity by moving the moving member to the position of the bottom part 25 of the cavity, the mold is clamped to blow a pressure fluid into the parison from the mouth part.