[Objective] The technical support for the development and utilization of lotus leaf ata large-scale was provided.[Method]The total flavonoids in lotus leaf were extracted with the ultrasound-assisted extraction method;its content was deter mined with spectrophotometric method and the optimum extraction process was studied through the single factor and orthogonal experiment.[Results] When the ethanol concentration was up to 60%,the largest yield of total flavonoids could be extracted;when the ration of the s...