This paper summarizes the research progress in pharmacological actions of liquorice and the proportion of couplet medicines in combination. Modern pharmacological studies have shown that liquorice and its active components have the effects of anti-oxidation, anti-inflammation, regulating immunity, anti-ulcer, detoxification, anti-cancer and anti-hepatic fibrosis etc. Liquorice not only has therapeutic effects when used alone, but also has different effects when used in combination with different drugs, such as liquorice-platycodon root, liquorice-peony root, liquorice-cassia twig, liquorice-rhubarb and so on.