Objective To develop a washing tube for minimally invasive treatment of sinus cavity pressure ulcer, and to observe its clinical effect. Methods Using transparent non-toxic PU plastic to make sinus cavity flushing and drainage tube, and with rounded hemispherical blunt head for the entry of the sinus, the perforated tube in the sinus cavity was designed with perforated holes (3 rows, 5 for each row); the end of the tube is blocked with heparin cap. The invented sinus cavity flushing tube was used for clinical observation and its use effect was observed. When used, the sinus cavity flushing drainage tube must be placed in the deepest antrum. The wounds were covered with PU sponge. By the active aspiration drainage of the negative pressure with sterile isotonic flushing fluid, bacteria, liquefied necrotic tissue, purulent secretion, internal and external toxins produced by bacteria, and the harmful material such as exudate of inflammatory medium in the sinus cavity was thoroughly removed. Results When treating sinus cavity and mixed pressure ulcer, minimally invasive treatment using the developed sinus cavity flushing drainage tube for irrigation and negative pressure drainage can significantly reduce patients' iatrogenic trauma, observably reduce the pain of the patients, shorten the treatment cycle, improve the cure rate of sinus pressure ulcers, and achieve good clinical effect. The sinus cavity flushing drainage tube has no damage to soft tissue, with simple operation and easy tolerance of patients. It is low price and using disposable materials, which can avoid cross-infection; It can be used to treat oxygen negative pressure in sinus cavity, and it has therapeutic effect on the sinus cavity pressure sore infected by anaerobic bacteria. It can be made into different specifications, different models, and widely used in different professional fields. Conclusion The sinus cavity flushing drainage tube combined with negative pressure treatment is a new technique of mild and undamaged cleansing wound, which makes up for the deficiency of flap surgery, and it is a very ideal method for minimally invasive treatment for sinus and cavity pressure ulcers.