It is desirable to identify predictors of regression of liver fibrosis after achieving sustained virological response by anti-hepatitisC virus (anti-HCV) therapy. We retrospectively investigated the serum interferon-γ inducible protein 10kDa (IP-10) level as a predictive indicator of regression of liver fibrosis after successful hepatitis C virus eradication by direct-acting antiviral agents (DAAs) therapy. The study participants were recruited from a historical cohort of 116 chronically hepatitisC virus-infected patients who had achieved sustained virological response by DAAs therapy and whose serum Mac-2 binding protein glycosylation isomer (M2BPGi) levels at baseline (before DAAs therapy) were ≥2.0 cut-off index. We defined patients with M2BPGi levels <1.76 and ≥1.76 cut-off index at 2years after the end of treatment (EOT) as the regression (n=71) and non-regression (n=45) groups, respectively. Multivariate analyses revealed that the albumin-bilirubin score at baseline, and albumin-bilirubin score, Fibrosis-4 index at 24weeks after the EOT, and serum IP-10 change from baseline to 24weeks after the EOT (IP-10 change) were significantly associated with regression of M2BPGi-based liver fibrosis. In addition, IP-10 change was significantly associated with regression of M2BPGi-based liver fibrosis by a multivariate analysis, even when the serum M2BPGi levels were aligned by propensity score matching and in patients with advanced M2BPGi-based liver fibrosis: M2BPGi levels ≥3.3 cut-off index at baseline. Serum IP-10 change from baseline to 24weeks after the EOT is a feasible predictor of regression of M2BPGi-based liver fibrosis after achieving sustained virological response with DAA therapy.