The invention discloses a traditional Chinese medicine composition for treating intractable skin diseases. The traditional Chinese medicine composition is prepared from the following raw materials inparts by weight: 80 to 120 parts of radix et rhizoma rhei, 35 to 60 parts of radix astragali, 10 to 30 parts of radix sophorae flavescentis, 10 to 15 parts of cortex dictamni, 5 to 12 parts of radix euphorbiae lantu, 8 to 15 parts of fructus cnidii, and 0.01 to 0.04 part of mylabris. The invention also discloses a preparation method and application of the traditional Chinese medicine composition for treating the intractable skin diseases. The traditional Chinese medicine composition has the advantages that the radix et rhizoma rhei, the radix astragali, the radix sophorae flavescentis, the cortex dictamni, the radix euphorbiae lantu, the fructus cnidii, and the mylabris are compounded according to a special ratio, so that the synergistic function is enhanced; the clinical test proves thatthe effect of treating various intractable skin diseases, such as dermatitis, eczema, psoriasis, onychomycosis and tinea of feet and hands is good; the irritation to skin is little, the effect is quickly taken, the effect is obvious, the easiness in recurrence is avoided, and any adverse reaction is avoided; the preparation technology is simple, the operability is high, the production cost is low,and the traditional Chinese medicine composition is suitable for large-scale production.