To provide a guide tube for a discharge device which can extract a cartridge from a tube body without removing a plunger from the tube body.

An escape part 24 is formed on the internal circumferential surface, at an apex, of the tube body 21. The escape part 24 is set to a length which allows the plunger 14 to find its way inside, when the plunger 14 is transferred toward the apex so far as the plunger 14 can reach a bottom 12 of a cartridge 1. The inside diameter of the escape part 24 is made slightly larger than the outside diameter of the apex of the tube part 11, into which the plunger 14 is fitted, or the outer circumferential surface, at the apex, of the tube part 11 is set to a size which allows the generation of a frictional resistance below a specified magnitude to the internal circumferential surface of the escape part 24.