Background and aims Rifaximin has been recommended as a prophylactic drug for hepatic encephalopathy (HE) and spontaneous bacterial peritonitis (SBP). This study aims to explore whether low-dose rifaximin can prevent overall complications and prolong survival in cirrhotic patients. Methods In this multi-centre randomized open-labelled prospective study, 200 patients with decompensated cirrhosis were randomly assigned at a ratio of 1:1. Patients in rifaximin group were administered 400 mg rifaximin twice daily for 6 months, and all other therapeutic strategies were kept unchanged in both groups as long as possible. The primary efficacy endpoints were the incidence of overall complications and liver transplantation-free survival. The secondary endspoints were the incidence of each major cirrhosis-related complication, as well as the Child-Pugh score and class. Results The major baseline characteristics were similar in the two groups except for HE. The cumulative incidence and frequency of overall complications were significantly lower in rifaximin group than in the control group (p < 0.001). Though liver transplantation-free survival was not significantly different between the two groups, subgroup analysis showed rifaximin markedly prolonged liver transplantation-free survival in patients with Child-Pugh score >= 9 (p = 0.007). Moreover, rifaximin markedly reduced the episodes of ascites exacerbation (p < 0.001), HE (p < 0.001) and gastric variceal bleeding (EGVB, p = 0.031). The incidence of adverse events was similar in the two groups. Conclusion Low-dose rifaximin significantly decreases the occurrence of overall complications, leading to prolonged survival in patients with advanced stages of cirrhosis in this trail. Further study should be carried out to compare the effect of this low-dose rifaximin with normal dose (1200 mg/day) rifaximin in preventing cirrhosis-related complications.