OBJECTIVE To explore the significance of quantitative digital subtraction angiography (DSA; Q-DSA) in the assessment of chemoembolization endpoints. METHODS Twenty patients with hepatocellular carcinoma treated with chemoembolization were included in the study. All DSA series before and after chemoembolization were postprocessed with Q-DSA. The maximal enhancement and time to peak (TTP) were measured for several homologous anatomic landmarks, including the origin and embolized site of the tumor-feeding artery, parenchyma of the tumor, and ostia of the pre- and postprocedure catheter. The TTP, tumor blood supply time, and maximal enhancement of the time density curve (TDC) were analyzed. RESULTS Of the 20 DSA series collected, 18 were successfully postprocessed. The TTPs of the landmarks before and after treatment were 3.60 seconds±1.02 and 3.57 seconds±0.78 at the ostia of the catheter, 3.91 seconds±1.01 and 4.09 seconds±1.14 at the origin site of the tumor-feeding artery, and 4.07 seconds±1.02 and 5.60 seconds±1.56 s the embolized site of the main tumor-feeding artery, respectively. Statistical differences were detected between pre- and postprocedural TTP of the embolized site of the feeding artery (P<.01), as well as between pre- and postprocedural tumor blood supply time (P<.01). The mean maximal TDC enhancements of selected tumor spots were 3.01 units±1.04 and 0.81 units±0.35 before and after the procedure (P<.01), respectively. CONCLUSIONS Q-DSA may provide a feasible quantitative measurement in the assessment of chemoembolization endpoints.