Abstract: OBJECTIVE To study the extraction technology of catechin from Catechu with ultrasonic process. METHODS Using the amount of catechin and epicatechin in dry extract as a major evaluation factor, orthogonal experiment was carried out to investigate four influential factors of the ethanol concentration, the ratio of raw material to solvent, the ultrasonic time and the extraction temperature. RESULTS The optimum condition of extraction from Catechu with ultrasonic technology was as follows, the concentration of ethanol, the ratio of raw material to solvent, the ultrasonic time, the extraction temperature were 50%, 1∶12, 35 min and 60 ℃, respectively. CONCLUSION The extraction process with ultrasonic method is fit for the extraction from Catechu with advantage of higher extraction rate and shorter time with less solvent and energy.