This paper selected 1 medical case from each of 16-year cases of recurrent attack of eczema, 8-year cases of psoriasis, 20-year cases of acne and 6-year cases of chloasma by Prof. Jiang Jianguo respectively, with 4 medical cases in total. This paper summarized Jiang's experience in the treatment of intractable skin diseases from the following three aspects：1) Gave priority to pattern differentiation, with reference to the characteristics of symptoms. He advocated making prescription based on pattern differentiation, according to disease and symptoms. 2) established the theory from pathogenic toxin and make proper use of insect drugs. He believed that skin disease is hard to treat due to interaction of dampness heat, blood stasis, phlegm dampness transforming into toxin. The treatment with simple clearing dampness, invigorating blood circulation often achieved little. The application of insect drugs can dispel wind and combat toxin with significant effect. 3) Apply the comprehensive combination of decoction and pill in the treatment based on the law of Treatise on Cold Damage. Remaining the essence of the principles of treatment instead of cling to the classical prescription, Prof. Jiang made good use of the diagnosis and treatment thought from Treatise on Cold Damage. Treating methods were leant from Zhang Zhongjing, and treating the chronic relapsing disease was often combined with decoction and pill.