The invention relates to a traditional Chinese medicine for treating sciatica, comprising the main components: 6g of angelica, 6g of red ginseng, 6g of hemlock parsley, 6g of earthworm and naze bead, 6g of homalomena rhizome, 6g of schizophragma integrifolium, 6g of prepared rhizome of rehmannia, 5g of pawpaw, 3g of cinnamon, 3g of coralbean bark, 9g of pseudo-ginseng, 9g of dried rhizome of rehmannia, 3g of cassia twig, 3g of notopterygium root, 3g of herba ephedrae, 60g of brown sugar, 10g of white spirit, and the like. The preparation method comprises the steps: airing the medicines; grinding the medicines into fine powder; putting the medicine powder and the brown sugar into a bottle; pouring the white sprit into the bottle; evenly mixing; sealing; and embedding the bottle underground for 7 days. The bottle is taken out when being needed. A prescription selects pure traditional Chinese medicines, materials are easy to take, the preparation method is simple, the taking and treating effects are good, and patients are not racked with pain. The traditional Chinese medicine for treating sciatica has low cost and is suitable for the treatment of poor families.