To analyze and explore medication rules of external use of Chinese materia medica in treating herpes zoster based on Data Mining.Methods:CNKI database was taken as retrieval database,with “SU = ‘herpes zoster’ and FT = ‘Chinese materia medica’ * ‘external use’” as the theme for advanced retrieval.Journal literature within fixed number of years for retrieval(January 1,2010 to December 1,2019)was selected.A database of Chinese materia medica in external treatment of herpes zoster was established.Retrieval results were screened out and analyzed by Excel and Clementine 12.0 software,and then medication rules and its possible mechanism of Chinese materia medica in the external treatment of herpes zoster were analyzed and explored.Results:In the past 10 years,a total of 116 compound prescriptions of Chinese materia medica were involved in the external treatment of herpes zoster in CNKI,involving a total of 184 kinds of Chinese materia medica,among which 52 kinds of Chinese materia medica were of high frequency.Borneolum Syntheticum,Radix et Rhizoma Rhei,Realgar,Cortex Phellodendri,etc.were frequently used.Four nature was mainly cold and warm; five flavors were mainly pungent and bitter; and channel tropism was mainly liver,heart and spleen.Heat-clearing medicines and blood-activating and stasis-removing medicines were widely used in the external treatment of herpes zoster by Chinese materia medica.A total of 16 medicine pairs were obtained by association analysis,among which Cortex Phellodendri-Radix et Rhizoma Rhei,Borneolum Syntheticum-Realgar,etc.were commonly used.Conclusion:In the external treatment of herpes zoster by Chinese materia medica,cold,warm,pungent and bitter medicines should be applied more.Corresponding Chinese materia medica should be selected for treatment,according to the principle of clearing heat,activating blood circulation and removing stasis.