Abstract: A blow-molding apparatus for molding hollow articles is disclosed, which comprises a base member, and a platform mounted thereon. An extruder is provided which has a nozzle located above the platform. Bearings are attached to the upper surface of the platform, and support a shaft. A mold opening/closing device is pivotable mounted on the shaft, and comprises a main body, a pair of mold halves supported by the main body, and a mold-moving unit for moving the molds toward and away from each other. The apparatus further comprises a device for rotating the mold opening/closing device around the shaft, thereby to incline the device at an angle, within a predetermined range, to the horizontal plane. Thus, both mold halves can be inclined, thereby forming an inclined cavity when they are clamped together. A parison can be supplied smoothly from the nozzle into the inclined cavity, under its own weight.