The invention provides a method for extracting an active component from rhizoma anemones raddeanae, wherein the method comprises the steps: after drying and dehydrating the rhizoma anemones raddeanae, carrying out ultramicro-pulverization; adding ethyl acetate, extracting, filtering to take the supernatant, carrying out reduced pressure concentration, then adding a methanol-aqueous solution, and carrying out ultrasonic dissolving; then separating on a silica positive phase preparative chromatography, and adopting a binary mobile phase containing A n-hexane and B ethanol, wherein the separation conditions comprise carrying out isocratic elution for 0-7 min with 100% A, carrying out isocratic elution for 7-27 min with 90% A and carrying out isocratic elution for 27-40 min with 5% A; and according to ultraviolet absorption spectra, collecting a 26-28 min eluate, carrying out reduced pressure concentration and drying to obtain the target active component. The separation method has the advantages of stability, high repeatability, large amount of preparation, and simple and time-saving operation, and is suitable for industrialized mass production; and the obtained active component can be used for preparing anti-lung cancer drugs or anti-tumor health-care products.