PURPOSE: To exactly close the holes of a porous plastic tube by a method in which the end of a porous plastic tube is heated for softening or melting, the inner wall or outer wall layer so softened or melted is pressed to form a pressed thin portion, and the pressed thin portion is inversely curled to close the hole in the end face.

CONSTITUTION: The end of a plastic tube 1 having an axially formed through hole 13 in the its wall is heated to soften or melt the end portion, and the inner wall layer 11 or outer wall layer 12 of the end portion so softened or melted is pressed for closing. The thin portion so pressed is inversely curled toward the inside or outside of the tube 1 to close a through hole 13 formed in the end portion of the tube 1. The through hole of the porous plastic tube can thus be exactly closed.