To study the material basis and analgesic mechanism of Lamiophlomis rotata(Benth.)kudo , a medicinal plant in xi-zang(tibet). Component were separated by extraction with solvent and gradient elution with macroporous adsorptive resin. Screening effective part of analgesic by acetic acid writhing and hot plate test in mice,and analysis the analgesic mechanism. Samples of separated by two methods have obviously analgesic pharmacological action to writhing reaction by acetic acid in mice,and could prolonged the...