Abstract: Objective To explore the significant risk factors associated with the all-cause mortality in patients with urosepsis secondary to ureteral obstruction manipulated by percutaneous nephrostomy. Methods Clinical data of 164 patients with urosepsis secondary to ureteral obstruction undergoing percutaneous nephrostomy were retrospectively analyzed. The risk factors of mortality rate before admission and within 30 d after discharge were analyzed. The significant variables identified by univariate analysis were subject to multivariate Logistic regression analysis. Results Eleven （6.7%） of 164 patients with urosepsis secondary to ureteral obstruction manipulated by percutaneous nephrostomy died during hospitalization or within 30 d after discharge. The mortality rate of patients with longer length of ICU stay was significantly increased （P = 0.001）. Patients with higher mortality rate presented with lower lymphocyte count, alkaline phosphatase, direct bilirubin, higher total bilirubin and Plasma osmolality（all P < 0.05）. Hydronephrosis, sequential organ failure assessment （SOFA） scores on the day of percutaneous nephrostomy and postoperative 2 d and the increase in SOFA score at 2 d after percutaneous nephrostomy were significantly correlated with the mortality rate （all P < 0.05）. Patients with higher respiration rate and quick SOFA （qSOFA） score after percutaneous nephrostomy showed higher mortality rate （both P < 0.05）. The changes of respiration rate before and after percutaneous nephrostomy, mental status and the changes of qSOFA scores before and after percutaneous nephrostomy were significantly correlated with the mortality rate （all P < 0.05）. Multivariate Logistic regression analysis showed that SOFA score at 2 d after percutaneous nephrostomy was significantly associated with the mortality rate （P = 0.001）. Conclusion SOFA score at 2 d after percutaneous nephrostomy is the most significant risk factor of the all-cause mortality rate in patients with urosepsis secondary to ureteral obstruction undergoing percutaneous nephrostomy.