The invention discloses a medicament for the treatment of sciatica and a preparation method, and belongs to the field of traditional Chinese medicines. The medicament disclosed by the invention comprises the following effective components: herbs of black medick, henry ormosia wood roots, vitis thunbergii, kadsura root-bark, ficus sarmentosa, bitter nightshade, cantonese speranskia, pine nodular branches, tarenna, rhaphidophora hongkongensis, stichopus japonicus, melaleuca leucadendron, herba chloranthi serrati, chloranthus serratus, erythrorchis altissima, and mahonia bealei carr. The medicament disclosed by the invention is appropriate in compatibility of selected herbs, meets the theories of traditional Chinese medicine and pharmacy and modern medicine and pharmacology, has the effects of dispelling wind and eliminating dampness, promoting blood circulation to arrest pain, and eliminating stasis to subdue swelling, and has a significant curative effect on sciatica; and the medicament is short in treatment course, easy to take, and safe, takes effect quickly, causes no recurrence after cure, and has no toxic or side effect, patients can work and live normally in the process of taking the medicament, and the medicament is practical and has a miraculous effect, therefore, the medicament is worth to be widely clinically applied.