To provide an apparatus for manufacturing a plastic hollow body wherein a mandrel can be surely pulled out without generating transverse deviation and longitudinal deviation and whose area of installation is small.

This apparatus for manufacturing a plastic hollow body has molds 6, a mandrel 28 being freely movably arranged in the axial direction in a cavity under a condition where these molds are combined and a mandrel moving apparatus 52 which moves the mandrel 28 in the axial direction in the cavity 25. The mandrel moving apparatus 52 has a moving truck 50 connected with the back end of the mandrel and has a driving shaft 54 being screwed in a driving plate 60 of the moving truck 50 and wherein a gear for moving a driving member 60 in the axial direction by rotating around the shaft is formed, a pair of running beams 56 holding the driving shaft 54 to freely rotate and being arranged approximately in parallel to both sides of the driving shaft 54 and a motor 58 for rotating the driving shaft 56.