A recent study revealed that quantitative hepatitis B core antibody (qAnti-HBc) level could serve as a novel marker for predicting treatment response. In the present study, we further investigated the predictive value of qAnti-HBc level in HBeAg-positive patients undergoing PEG-IFN therapy. A total of 140 HBeAg-positive patients who underwent PEG-IFN therapy for 48 weeks and follow-up for 24 weeks were enrolled in this study. Serum samples were taken every 12 weeks post-treatment. The predictive value of the baseline qAnti-HBc level for treatment response was evaluated. Patients were further divided into 2 groups according to the baseline qAnti-HBc level, and the response rate was compared. Additionally, the kinetics of the virological and biochemical parameters were analyzed. Patients who achieved response had a significantly higher baseline qAnti-HBc level (serological response [SR], 4.52 +/- 0.36 vs. 4.19 +/- 0.58, p=0.001; virological response [VR], 4.53 +/- 0.35 vs. 4.22 +/- 0.57, p=0.005; combined response [CR], 4.50 +/- 0.36 vs. 4.22 +/- 0.58, p=0.009)). Baseline qAnti-HBc was the only parameter that was independently correlated with SR (p=0.008), VR (p=0.010) and CR(p=0.019). Patients with baseline qAnti-HBc levels >= 30,000 IU/mL had significantly higher response rates, more HBV DNA suppression, and better hepatitis control in PEG-IFN treatment. In conclusion, qAnti-HBc level may be a novel biomarker for predicting treatment response in HBeAg-positive patients receiving PEG-IFN therapy.