Abstract:Proanthocyanidins is one of the best free-radical scavengers we have discovered so far，which is rich in the Viburnum odoratissimum leaf and its effective extraction has important economic value.Single factor experiment and response surface methodology（RSM）were adopted to study the effects of ethanol concentration，liquid/solid ratio，ultrasonic treatment time on the extraction rate of proanthocyanidin from Viburnum odoratissimum leaf （VOL）.A multiple regression model was established to optimize the parameters for ultrasonic-assisted extraction of VOL.The results indicated the optimum extraction conditions of proanthocyanidins inside VOL were as following：ethanol concentration was 85%，the solid-liquid ratio was 1/40（g/mL）and extraction time was 37 min.In such case，the highest extraction rate was 16.92%，which was close to the model-predictive value.Our results indicated that the developed model had good regression performance and fitness，and could be applied in the prediction of the extraction yield of VOL.This study could provide scientific data for the application of VOL as a natural proanthocyanidins source.