The invention provides an adjustable glaucoma drainage tube.The adjustable glaucoma drainage tube comprises a hollow wide rubber tube arranged close to the equator portion of an eyeball, a movable inner core and a thin drainage tube body.Inner tubes with the same length are arranged in the hollow wide rubber tube in the length direction of the hollow wide rubber tube.Several micropores perpendicular to the inner tubes are formed in the wall of the hollow wide rubber tube to make the inner tubes communicate with the outer portion of the hollow wide rubber tube.The tail end of the thin drainage tube body is communicated with the inner tubes of the hollow wide rubber tube, and the front end of the thin drainage tube body is inserted in an anterior chamber.The front end of the movable inner core swells to prevent aqueous fluid from continuing to be drained to the far ends of the inner tubes of the hollow wide rubber tube.After an operation, the length of a cavity in the front end of the hollow wide rubber tube is adjusted by adjusting the position of the movable inner core, and then the aqueous fluid drainage volume is adjusted; the movable inner core is pulled out to increase the volume of the aqueous fluid drained into inner cavities of the hollow wide rubber tube, and the intraocular pressure of orbital tissue is reduced; when the movable inner core is pushed to the near end, the volume of the aqueous fluid drained into the inner cavities of the inner tubes is reduced, and then the intraocular pressure is increased.According to the device, the aqueous fluid drainage volume can be adjusted according to clinical needs after the operation, half quantitative adjustment can be carried out, and therefore the purpose of adjusting the intraocular pressure is achieved.