The present invention relates to a preparation method of carthamus extract. Said method includes the following steps: soaking carthamus flower in warm water to obtain extract A; concentrating the extract A to obtain concerrtrate, separating said concentrate by means of macroporous adsorbing resin, then successively using water and alcohol to make elution, collecting eluted portion by using alcohol, reeovering eluent until the alcohol content is below 25% so as to obtain eluent B; using ceramic membrane to make ultrafiltration so as to obtain ultrafiltrate C; decompressing ultrafiltrate, recovering solvent to obtain heavy paste, drying so as to obtain the invented product. Said extract is characterized by that total carthamus yellow content is greater than 80%, hydroxyl carthamus yellow A content is greater than 20% and kaempferol-3-0-rutinoside content is greater than 0.6%. |