Objective To research the meaning of ‘only one symptom’according to Xiaochaihu Decoction（小 柴胡汤）cases.Methods The data was processed with data mining and frequency analysis.Results Totally 147 medical cases were included.The top 8 main symptoms were bitter mouth

loss of appetite

nausea

cold and heat exchanges

dry throat

dizziness

chest pain full and upset.Only four main symptoms such as cold and heat exchanges

chest pain full

loss of appetite and upset had medical cases.Conclusion Seven symptoms have diagnostic significance in Xiaochaihu Decoction（小柴胡汤）pattern such as bitter mouth

dry throat

dizziness

cold and heat exchanges

chest pain full

loss of appetite and upset.’But see a pattern’ means one of the four symptoms such as cold and heat exchanges

chest pain full

upset and loss of appetite.