A method of making a catheter tube includes extruding a first resin having a first predetermined rigidity through a first extruder； extruding a second resin having a second predetermined rigidity through a second extruder； controlling a mixing ratio of the first and second resins extruded from the first and second extruders； and molding the first and second extruded resins to form an integrally molded tube having at least a first region, a second region which possesses a rigidity greater than the first region, and a transition region between the first region and the second region and which possesses a rigidity varying from the same rigidity as the rigidity of the first region to the same rigidity as the rigidity of the second region.
