A resin composition formed by mixing 99 to 70 weight % of specific whole aromatic polyesteramide liquid crystal resin (A) with 1 to 30 weight % of epoxy modified polyolefin-base resin (B) and by melting and kneading both of the resins, wherein the resin composition having a melt viscosity of 60 to 4000 Pa·s at a shear rate of 1000/second at a temperature which is 20° C. higher than the melting point and having a melt tension of 20 mN or more at a take-over speed of 14.8 m/minute, is melt within a temperature range of a melting point to the melting point +40° C., a parison (P) is formed by extruding it with an extrusion speed equal to or higher than 0.3 kg/minute and lower than 5 kg/minute, a pair of moldings placed so as to sandwich the parison (P) are closed at a predetermined mold closing pressure, and air is blown into the parison (P).