Data comparing the efficacy and safety of combination therapy with peginterferon plus low-dose ribavirin and peginterferon monotherapy in treatment-naive haemodialysis patients with hepatitis C virus genotype 2 (HCV-2) infection are limited. In this randomised trial, 172 patients received 24 weeks of peginterferon alfa-2a 135 μg/week plus ribavirin 200 mg/day (n=86) or peginterferon alfa-2a 135 μg/week (n=86). The efficacy and safety endpoints were sustained virological response (SVR) rate and adverse event (AE)-related withdrawal rate. Compared with monotherapy, combination therapy had a greater SVR rate (74% vs 44%, relative risk (RR): 1.68 [95% CI 1.29 to 2.20]; p<0.001). The beneficial effect of combination therapy was more pronounced in patients with baseline viral load ≥800,000 IU/mL than those with baseline viral load <800,000 IU/mL (RR: 3.08 [95% CI 1.80 to 5.29] vs. RR: 1.11 [95% CI 0.83 to 1.45]; interaction p=0.001). Patients receiving combination therapy were more likely to have a haemoglobin level of <8.5 g/dL (70% vs. 8%, risk difference (RD): 62% [95% CI 50% to 73%]; p<0.001) and required a higher dosage [mean: 13,417 vs. 6667 IU/week, p=0.027] of epoetin β to manage anaemia than those receiving monotherapy. The AE-related withdrawal rates were 6% and 3% in combination therapy and monotherapy groups, respectively (RD: 2% [95% CI -4% to 9%]). In treatment-naive haemodialysis patients with HCV-2 infection, combination therapy with peginterferon plus low-dose ribavirin achieved a greater SVR rate than peginterferon monotherapy. Most haemodialysis patients can tolerate combination therapy. ClinicalTrial.gov number, NCT00491244.