Abstract: Based on hydrophilic alcohol-salt aqueous two-phase system, a rapid and efficient method for extraction and purification of triterpenoids from Ganoderma lucidum was constructed with methanol/K₃PO₄.The type of hydrophilic alcohol, inorganic salt (type, concentration, pH), the amount of Ganoderma lucidum extract, the pH of the lower phase was investigated by using the single factor experiment. Subsequently, orthogonal design methodology was used to explore the optimal extraction condition, the solution concentration of K₃PO₄, the amount of the extractive, the pH of the lower phase was chosen as the L₉ (3⁴)experimental factor. The optimal condition was 10.6% K₃PO₄, 42.5% methanol, 5% Ganoderma lucidum extractive, the pH of the lower phase was adjusted to 4.0 after removing the upper phase. Under these conditions, (10.13±0.19) mg/g Ganoderma lucidum triterpenoids were obtained, which was 36.5% higher than that prepared by the traditional method (7.42±0.09) mg/g. The methanol/K₃PO₄ aqueous two-phase system is a simple, efficient method for extraction and purification triterpenoids from Ganoderma lucidum.