The feature of the invention includes: adopting frozen chicken gallbladder slicing, heating to 70 degree centigrade, adding 10% weight of the bile boiling for 24 hours, reflux cooling, adjusting the pH value by hydrochloric acid to gain cream, washing to neutrality; adding 95% alcohol and 10% diatomite, reflux cooling and adding active carbon, reflux, cooling and filtering, adding petrol to the filtrate to take degreasing, reflux, standing, separating alcohol liquid and washing to neutrality in reaction kettle, adding 95% alcohol, after resolving, adding barium chloride and active carbon, reflux, hot filtering, concentrating white crystal from the filtrate, washing, and adding water and sodium carbonate water solution, heating and reflux, filtering, adjusting the pH value, drying. The invention has simple technology, low cost, and could drastically separate cholesterol, lithocholic acid, and cholic acid from gall, and improves the purity.