PURPOSE: To provide a core bar which can bend a tubular material easily three dimensionally, prevent deformation of a cross-sectional shape and draw the tubular material easily.

CONSTITUTION: The core bar 20 consists of solidly bundled wires 21 which are fixed mutually at the terminals on one side and a cover 22 by which these terminals are clamped fixedly. A female screw is provided and a pulling metal 24 is mounted on the fixed en face. Each wire 21 is curved freely, therefore, though the tubular material is curved three-dimensionally, it follows the curved shape and the total cross sectional area of the bundled wires 21 is fixed at any part, consequently, the cross-sectional shape of the tubular material can be prevented from being deformed. Further, when the pulling metal 24 is pulled, this core bar 20 can be inserted easily into the tubular material or drawn easily after it is bent.