The invention provides a preparation method of the total flavone from the natural plant, belonging to the technical field of the plant. The method comprises the steps of: taking the aeschynanthus moningeriae as a raw material, and taking alcohol containing water as dissolvent to extract the tissue in a breaking way; filtering in a pumping way, merging filter liquor, and recovering the dissolvent by means of flashing and concentrating; and separating and enriching the obtained concentrated liquor by macroporous absorption resin, performing gradient elution on the alcohol containing water, merging the eluent of the alcohol containing water with a certain proportion to recover the dissolvent by means of flashing and concentrating, and continuously performing the vacuum drying on the solvent to obtain dried powder so as to obtain the total flavone extractive of the aeschynanthus moningeriae. The preparation method is simple in technology, advanced in extraction and concentration technology, convenient in operation, low in cost, green and high-efficiency, so that the total flavone content in the extractive is 32.27%-43.69%, the extracting rate is 8.56%-13.56%, and the transferring rateis as high as 72.33%-84.45%. The preliminary extracorporeal bioactivity test shows that the specific total flavone extractive of the aeschynanthus moningeriae has a certain antibacterium activity andantioxidation activity.