The optimal prognostic assessment for patients with hepatocellular carcinoma (HCC) after drug-eluting bead transarterial chemoembolization (DEB-TACE) remains unclear. This study aimed to propose a novel staging system in comparison with the current staging systems for HCC following DEB-TACE. From four centers, patients with HCC undergoing DEB-TACE as the initial therapy were retrospectively included and classified into training and validation sets. Multivariable regression was used to determine the independent prognostic factors in the training set. A novel staging system incorporating the independent factors was proposed and externally validated in terms of discrimination and calibration compared to other staging systems in both sets. The training and validation sets included 335 and 99 patients, respectively. Multivariable regression revealed independent factors including alpha-fetoprotein level, aspartate aminotransferase to lymphocyte count ratio index, maximum tumor diameter, Child-Pugh class, and portal vein invasion. The novel prognostic staging system, named PADCA, was proposed and outperformed other staging systems with the highest C-index, area under the curve, Wald test value, clinical benefit, and the lowest Akaike information criterion in the training and validation sets. The PADCA staging system has a superior prognostic predictive ability compared to the current staging systems. PADCA can assist clinicians in screening out the patients most likely to derive benefit from DEB-TACE and guiding the formulation of therapy and follow-up strategy.