Objective: To investigate the related risk factors in patients with decompensated cirrhosis complicated with sepsis. Methods: 1 098 cases with decompensated cirrhosis were collected from January 2018 to December 2020. A total of 492 cases with complete data meeting the inclusion criteria were included. Among them, the sepsis group (240 cases) was complicated with sepsis and the non-sepsis group (252 cases) was not complicated with sepsis. Albumin, cholinesterase, total bilirubin, prothrombin activity, urea, creatinine, international normalized ratio and other indicators of the two groups of patients were collected. Child-Pugh classification and MELD score were performed on two groups of patients. Mann-Whitney U test was used for non-normally distributed measurement data, and rank sum test for grade data. Logistic regression analysis was performed on sepsis-related factors that may affect patients with decompensated cirrhosis complicated with sepsis. Results: 162 cases of gram negative bacteria, 76 cases of gram positive bacteria and 2 cases of Candida were detected. Child-Pugh grade C was mainly in the sepsis group, and Child- Pugh grade A and B was mainly in the non-sepsis group (z=-13.01, P<0.05). MELD score was significantly higher in patients with sepsis than that of patients without sepsis (z=-12.30, P<0.05). Neutrophils percentage, C-reactive protein, procalcitonin, and total bilirubin in patients with decompensated cirrhosis complicated with sepsis were 86.90% (79.00%, 91.05%), 48.48 (17.63, 97.55) mg/l,1.34 (0.40, 4.52) ng/l, and 78.50 (32.75149.80) μmol/L, which were significantly higher than that of patients without sepsis [69.55% (58.58%, 75.90%), 5.34 (5.00, 14.94) mg/l, 0.11(0.06,0.24) ng/l, 22.50(15.10,37.55) respectively] μmol/L, P<0.05], while the albumin level, prothrombin activity level, and the cholinesterase level in sepsis patients were 27.30 (24.45, 30.60) g/L, 46.00% (33.50%, 59.00%), and 1.87 (1.29, 2.66) kU/L, respectively, which was significantly lower than the non-sepsis group [32.65 (28.95, 37.23) g/l, 73.00(59.75~84.85)%, 3.13(2.23~4.59) kU/L, P<0.05]. Logistic regression analysis showed that serum total bilirubin, albumin, prothrombin activity level and diabetes mellitus were the independent risk factors for complicated sepsis. Conclusion: Patients with decompensated cirrhosis with poor liver function and higher MELD scores are more likely to be complicated with sepsis. Therefore, during the clinical diagnosis and treatment course, patients with decompensated cirrhosis with poor liver reserve function should be actively and dynamically monitored for infection-related indicators such as neutrophil percentage, procalcitonin, C-reactive protein, in an attempt to detect possible potential infections and sepsis, and improve early treatment and prognosis.