To provide an apparatus and a method for sealing an end of a flexible tube with which a form of a seal end can be formed in an arbitrary shape by a simple operation either for a single-layered tube or a multi-layered tube, an opening end can be smoothly machined, wherein sealing strength is stable and the apparatus and the method are suitable for production of numerous kinds in small quantities due to frequent modification.

The apparatus includes devices for hermetically sealing open ends of a flexible tube P, including a clamping device 10 for temporarily clamping after a position of an open end P1 is adjusted, a cutter 20 for cutting the temporarily clamped open end P1 in an arbitrary shape, a fusing device 30 for fusing the cut open end P1, and an end sealer 40 for contact-bonding the fused open end P1 for sealing. The cutter 20 includes a fixed edge 21 for integrally cutting from both ends of the temporarily clamped open end P1 toward an upper end or an regulating edge for cutting from both ends toward the upper end in a free form.