Objective To study pattern characteristic of IgA nephropathy with qi-yin deficiency through clinical data mining.Methods Clinical data mining was done by frequency and factor analysis.Results（1）The cardinal symptoms of IgA nephropathy were aching lumbus and knees

fatigue and lack of strength

dry pharynx

pharyngalgia

heat in the heart of the palms and soles

easily to catch a cold

fear of cold

dry eyes

dizziness

spontaneous sweating

torpid intake

dry stool and night sweating in order.Red

partial red or red-tipped and margined tongue was the most frequently appeared sign indicating inner heat

and then pale red tongue indicating equal qi and yin deficiency.（2）Factor analysis resulted in 3 common factors.The root value of F1 was the highest.Symptoms of F1 were similar to tending toward yin deficiency pattern and located in the liver

spleen and kidney.It indicated that the rate of qi-yin deficiency tending toward yin deficiency pattern was highest.Symptoms of F2 were similar to equal qi and yin deficiency pattern and located in the spleen and kidney.Symptoms of F3 were similar to tending toward qi deficiency pattern and located in the lung and spleen.Conclusion Tending toward yin deficiency and equal qi and yin deficiency patterns are common in IgA nephropathy patients with qi-yin deficiency.