To provide a production method for a corrugated tube by which the smooth finish of a tube inner surface is obtained even in the case of small diameter of the tube and also the tube wall with good flexibility having a multilayered structure can be produced.

This production method for the corrugated tube comprises a process for extruding a multilayered molding material from an annular nozzle, a process for feeding the extruded tubular material (10) into the corrugating passage of a corrugation die, and a process for sucking the periphery of the extruded tubular material (10) from the corrugating groove of the die to corrugate the tube wall of the material (10). In the tubular material (10), either one of inner layers except an outer layer (12) is formed of a foaming layer (13), the foaming force of which is regulated to offset the sucking force of the corrugating groove.

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