The invention relates to a compound Chinese medicament for treating sciatica and a preparation method thereof. The compound Chinese medicament mainly comprises large-headed atractylodes rhizome, dahurian angelica root, processed tuber fleeceflower root, corydalis tuber, Szechuan lovage rhizome, processed aconite main tuber, costus root, fennel, medicinal cyathula root and Chinese quince; and the raw materials are extracted according to the physicochemical properties of effective ingredients of each gout of medicament, and the extract is prepared into oral solid or liquid formulation according to a conventional method. The Chinese medicament has the effects of warming center and dissipating cold, tonifying spleen and clearing damp, promoting blood circulation and qi circulation and relieving pain. Clinical experiments prove that the compound Chinese medicament has definite curative effect on the sciatica, short response time and no toxic or side effect.