The present invention relates to a traditional Chinese medicine bath composition for treating psoriasis, its preparation method and application. Rib, curcuma, safflower, salvia, bletilla striata, notoginseng, wild chrysanthemum, Sichuan pepper, mugwort leaves. The beneficial effects of the present invention are: the traditional Chinese medicine soaking bath composition for treating psoriasis described in the present invention has better functions of promoting blood circulation and removing blood stasis, killing insects and relieving itching, clearing heat and detoxification, reducing swelling and relieving pain. Supplemented with medicated baths, with the combined effect of temperature and drugs, it can warm and dredge the meridians, circulate qi and blood, restore the nutrient blood and circulate unimpeded, and the skin can be nourished and diseased and healed. The composition of the invention has remarkable effect in treating psoriasis, quick effect, convenient use, high safety, wide adaptability, and no drug dependence, and is suitable for popularization and utilization.