Objective: To compare effects of traditional decoction method and modern decoction method on active ingredients yield and extract yield of Gegen Qinlian decoction. Method: Taking yield of dry extract and contents of twelve active components as indexes

different values of medication in classical formulas included one ounce equals to13.8 g and one ounce equals to 3 gram were adopted

effects of two different decoction methods on quality of Gegen Qinlian decoction were investigated by single factor tests. Result: When one ounce equals to13.8 g

compared with modern decoction method

contents of active components by traditional decoction method reached 47%-74%

dry extract rate was 67%;When one ounce equals to 3 g

compared with modern decoction method

contents of active components by traditional decoction method reached 102%-148%

dry extract rate was 118%. Conclusion: Different decoction methods with different values of classic formulas had effects on contents of active components

this study could provide a reference for making the past serve the present of classical prescriptions.