PURPOSE: To safely and surely cut the cover film of a covered tube in the peripheral direction and the longitudinal direction by providing a guide projection entering the groove of the covered tube and moving a side cutting edge along the groove when a hold section is rotated around the axis of the covered tube on the hold section.

CONSTITUTION: A side cutting edge 9 cutting a cover film 2 in the peripheral direction is arranged at the position faced to the groove 3 of a covered tube 1 in the holding space of a hold section 5 receiving and holding the covered tube 1 from the side section. A guide projection 8 entering the groove 3 and moving the side cutting edge 9 along the groove 3 when the hold section 5 is rotated around the axis P of the covered tube 1 is provided on the hold section 5. A vertical cutting edge 12 moved in the longitudinal direction of the pinched covered tube 1 together with the hold section 5 to cut the cover film 2 in the longitudinal direction is provided on the base end side of the guide projection 8. A film guide section 13 entering the cut end in the peripheral direction of the cover film 2 along the groove 3, scooping the cover film 2 when the vertical cutting edge 12 is moved along the cutting direction, and guiding it to the vertical cutting edge 12 is provided on the tip side of the vertical cutting edge 12.