Objective To learn if there were different characteristics of tongue demonstration between diseases caused by exogenous pathogenic factor and disorder of internal organs. Methods Choosing 3059 cases from 51 medical records of Qing Dynasty, in which 1397 cases were diagnosed as diseases caused by exogenous pathogenic factor and 1110 were disorder of internal organs. Contrasting the constituent ratio of tongue demonstration using chi-square test. Results There were significant deviation between diseases caused by exogenous pathogenic factor and disorder of internal organs in color of tongue, color of fur and quality of fur (p<0.01). Conclusions the characteristics of tongue demonstration in diseases caused by exogenous pathogenic factor were high frequency of bright red tongue, yellow fur, blank fur and dry fur; and which in disorder of internal organs were high frequency of white tongue, thin fur, greasy fur and exfoliative fur.