NOVELTY - Preparing jatrorrhizine from traditional Chinese medicine comprises (i) adding medicinal materials into a container, grinding, adding acidic aqueous solvent, refluxing, filtering, recovering solvent, adjusting pH using alkali, placing statically, filtering, concentrating the filtered liquid, filtering and drying to obtain precipitate, where the medicinal material comprises e.g. herba fibraureae recisae, Berberis and radix tinosporae, (ii) refluxing and extracting with aqueous alkali solvent, and (iii) repeatedly extracting using aqueous alkali solvent.    USE - The jatrorrhizine is useful for preventing and treating colon cancer (claimed).    ADVANTAGE - The method produces more than 80% jatrorrhizine (claimed), has short period, and is economical, environmentally friendly and suitable for industrial production.    DETAILED DESCRIPTION - Preparing jatrorrhizine from traditional Chinese medicine comprises (i) adding medicinal materials into a container, grinding, adding acidic aqueous solvent, refluxing, filtering, recovering solvent, adjusting pH using alkali, placing statically, filtering, concentrating the filtered liquid, adjusting pH using acid, adding 5-30% sodium chloride, placing statically, filtering and drying to obtain precipitate, where the medicinal material comprises leatherleaf mahonia, golden cypress, herba fibraureae recisae, Coptis root, Berberis and radix tinosporae, (ii) dissolving the precipitate in aqueous alkali solvent, refluxing and extracting, filtering, adjusting pH of filtered liquid using alkali, placing statically, filtering, concentrating the filtered liquid, adjusting pH using acid, adding 5-30% sodium chloride, placing statically, filtering and drying to obtain precipitate, and (iii) repeatedly repeating step (ii), dissolving the precipitate using aqueous alkali solvent, refluxing and extracting, filtering to obtain the precipitate, dissolving the precipitate in aqueous solvent, filtering, concentrating the filtered liquid, adding 0-30% of sodium hydroxide, placing statically, filtering and drying the precipitate to obtain jateorrhizine.