Abstract: The 95% ethanol extract of llicium micranthum was separated and purified by silica gel, Sephadex LH-20, MCI-gel and semi-preparative HPLC. The chemical structures of the isolated compounds were identified by NMR and MS. Twelve compounds were isolated and identified as illimicranol A (1), vanilloloside (2), 4-O-β-D-glucosyl-benzoic acid (3), gastrodin (4), icariside D₂ (5), caryolane-1,9β-diol (6), clovane-2β,9α-diol (7), methyl shikimate (8), protocatechuic acid methyl ester (9), p-hydroxybenzyl alcohol (10), p-hydroxyphenylethanol (11), methyl p-hydroxyphenylacetate (12). Among them, compound 1 is a unique lignan with new carbon skeleton, named illimicranol A. Compounds 2-12 are firstly isolated from this plant. The effects of compound 1 on the differentiation of PC12 cells induced by NGF and the damage of PC12 cells induced by MPP⁺ were evaluated. The results showed that compound 1 did not exhibit obvious neurotrophic and neuroprotective activities.