A thermally shrinkable tube heating apparatus, comprising: a holding member including an accommodation space capable of accommodating a thermally shrinkable tube and being capable of grasping the thermally shrinkable tube accommodated in the accommodation space; and a hot air generation device generating hot air, wherein: the holding member includes: a wall provided around a predetermined axis (Ax), extending in an axial direction of the axis (Ax), and forming the accommodation space inner thereto, an inlet flow path including a supply opening (R3a) opened to an outer surface of the holding member and an inlet opening (R3b) opened to the wall, and a discharge flow path including an outlet opening (R1a) opened to the wall and a discharge opening (R1b) opened to the outer surface of the holding member, and the hot air generation device sends the hot air into the supply opening (R3a), characterized in that the holding member includes a plurality of clamp members (41L, 41R) each including a part of the wall, the thermally shrinkable tube heating apparatus further includes: a driving device driving the plurality of clamp members (41L, 41R) in a radial direction of the accommodation space to cause the plurality of clamp members (41L, 41R) to grasp or release the thermally shrinkable tube accommodated in the accommodation space. a holding member including an accommodation space capable of accommodating a thermally shrinkable tube and being capable of grasping the thermally shrinkable tube accommodated in the accommodation space; and a hot air generation device generating hot air, wherein: the holding member includes: a wall provided around a predetermined axis (Ax), extending in an axial direction of the axis (Ax), and forming the accommodation space inner thereto, an inlet flow path including a supply opening (R3a) opened to an outer surface of the holding member and an inlet opening (R3b) opened to the wall, and a discharge flow path including an outlet opening (R1a) opened to the wall and a discharge opening (R1b) opened to the outer surface of the holding member, and the hot air generation device sends the hot air into the supply opening (R3a), characterized in that the holding member includes a plurality of clamp members (41L, 41R) each including a part of the wall, the thermally shrinkable tube heating apparatus further includes: a driving device driving the plurality of clamp members (41L, 41R) in a radial direction of the accommodation space to cause the plurality of clamp members (41L, 41R) to grasp or release the thermally shrinkable tube accommodated in the accommodation space. the holding member includes: a wall provided around a predetermined axis (Ax), extending in an axial direction of the axis (Ax), and forming the accommodation space inner thereto, an inlet flow path including a supply opening (R3a) opened to an outer surface of the holding member and an inlet opening (R3b) opened to the wall, and a discharge flow path including an outlet opening (R1a) opened to the wall and a discharge opening (R1b) opened to the outer surface of the holding member, and the hot air generation device sends the hot air into the supply opening (R3a), characterized in that a wall provided around a predetermined axis (Ax), extending in an axial direction of the axis (Ax), and forming the accommodation space inner thereto, an inlet flow path including a supply opening (R3a) opened to an outer surface of the holding member and an inlet opening (R3b) opened to the wall, and a discharge flow path including an outlet opening (R1a) opened to the wall and a discharge opening (R1b) opened to the outer surface of the holding member, and the hot air generation device sends the hot air into the supply opening (R3a), characterized in that the holding member includes a plurality of clamp members (41L, 41R) each including a part of the wall, the thermally shrinkable tube heating apparatus further includes: a driving device driving the plurality of clamp members (41L, 41R) in a radial direction of the accommodation space to cause the plurality of clamp members (41L, 41R) to grasp or release the thermally shrinkable tube accommodated in the accommodation space.