By the aid of the surface activities of glycyrrhizic acid, foam separation can be used to extract and concentrate it. The effects of operating parameters such as flow rate of air, initial feed concentration, pH and ionic strength on the enrichment ratio and recovery yield of glycyrrhizic acid are investigated in detail. In addition, the influences of other surface-active substances in solution, such as proteins, on the separation of glycyrrhizic acid are also discussed. The experimental results show that foam separation is a simple and effective method to separate and concentrate glycyrrhizic acid.