Published data on retreatment with pegylated interferon and ribavirin of previously failing HIV-HCV coinfected patients are sparse and limited to observational study. We aimed to evaluate efficacy and pretreatment predictors. Systematic review and meta-analysis of observational studies. The overall and genotype-related success rate was investigated. A direct comparison was performed between genotypes 1/4 and 2/3 by evaluating the sustained virological response (SVR) rate ratio (RR). The effect of study level variables on the effect size was investigated by meta-regression. Variables that were analyzed included age, gender, advanced hepatic fibrosis, pretreatment of HCV RNA and CD4, and successful antiretroviral treatment (ART). The available evidence was from 5 open-label, cohort studies (275 patients). The overall SVR rate was 0.280 (95% CI,0.171-0.425). The SVR rate in genotype 1/4 infections was 0.174 (95% CI, 0.129-0.230), and in genotype 2/3 infections it was 0.474 (95% CI, 0.286-0.670). The pooled RR comparing the SVR of genotype 1/4 to 2/3 was 0.369 (95% CI, 0.239-0.568), with a decreased probability of response for genotype 1/4 (P < .001). HIV RNA suppression had a significant effect on SVR (P = .005). The other covariates had no effect on the overall SVR rate. The overall SVR rate was 28%, consistent with the rate reported in the retreatment of mono-infected patients with the same schedule. A substantial relative reduction in the SVR rate of about one-third, when treating genotypes 1/4, was found, with a low SVR rate of 17%. Successful HIV suppression by ART predicted a higher rate of treatment success.