Objective:To summarize the application of phage therapy in patients with urinary tract complicated pandrug-resistant Klebsiella pneumoniae infection, and analyze its feasibility and effectiveness.Methods:To retrospectively analyze the clinical data of a patient with complicated urinary tract complex pan-resistant Klebsiella pneumoniae treated by phage from August to September, 2019 in Shanghai Public Health Clinical Center. The female patient, 65 years old, was admitted to the hospital on August 6, 2020. The patient repeated with frequent micturition and urgent micturition half a year before admission. These symptoms were not accompanied by back pain, fever, chills, dysuria, gross hematuria. Urinary culture results in outpatient hospital was pan-resistant Klebsiella pneumoniae. After the patient discontinued application of cefoperazone sulbactam, levofloxacin and other drugs, symptoms such as frequent urination could be relieved after treatment, but appeared repeatedly. In August 2019, the center innovatively applied phage therapy to treat this patient with urinary tract pandrug-resistant bacteria infection.Results:For the first time, we applied 117, 135, 178, GD168 phage mixed solution once a day, for 5 days of continuous bladder infusion. At the same time, meropenem and amikacin was intravenous administration to strengthened the anti-infection treatment. Urine culture was negative for two consecutive times after treatment. However, half a month after the end of the bladder infusion, the patient experienced discomfort such as frequent urination. Urine culture: pan-resistant Klebsiella pneumoniae. The second time, we applied a mixture of three phage strains 130, 131, 909, once a day, for 5 days of continuous bladder infusion. And in the afternoon of the third day of treatment, the renal pelvis was retrogradely intubated and perfused with the above three strains of phage mixture. During the second treatment follow-up until March 30, 2020, the patient's urine culture was reviewed once a month. As a result, no pan-resistant Klebsiella pneumoniae was found, and the patient no longer experienced frequent urination and other symptoms of urination. The treatment process was successful and without severe complications and side effects.Conclusions:Phage urinary tract perfusion is an effective method for the treatment of pan-resistant Klebsiella pneumoniae urinary tract infections. The curative effect is accurate and reliable. The patient did not show obvious complications and adverse reactions during treatment. It can be used as an alternative treatment plan for complex pan-resistant Klebsiella pneumoniae infection.