Objective: To analyze the application of Rhizoma Coptidis-Cortex Magnoliae Officinalis herbal pair compatibility

reveal its compatibility law and provide reference for clinical use. Method: Totally 475 formulae containing Rhizoma Coptidis-Cortex Magnoliae Officinalis herbal pair were retrieved from the 'Traditional Chinese Medicine Formula Database' established by Institute of Information on Traditional Chinese Medicine

China Academy of Chinese Medical Sciences. Then a new database was built to analyze the compatibility ratio

corresponding major diseases and major departments for the herbal pairs. Result: In the 475 formulae

ratio ‘1: 1’ of Rhizoma Coptidis and Cortex Magnoliae Officinalis appeared to be the most (215 times

45.26%); the most frequent disease genus was internal medicine (329 times

69.26%); in the formulae for common colds and flu

ratio ‘1: 1’appeared to be the most (10 times

50%). Conclusion: The data analysis methods such as frequency statistics for the compatibility law and application rules of herbal pairs can provide a theoretical basis for clinical application.