Ten phenanthrenes, two organic acids, one organic acid ester and one flavonoid were isolated from the aerial part of Juncus setchuensis by various chromatographic techniques usingsilica gel, polyamide, Sephadex LH-20 as solid phases, and preparative HPLC. Their structures were identified by MS and NMR spectroscopic data as effusol(1), juncusol(2), juncuenin D(3), dehydroeffusol(4), dehydrojuncusol(5), juncuenin B(6),dehydrojuncuenin B(7), 2-methoxyl-7-hydroxyl-1-methyl-5-vinyl phenanthrene(8), 2-hydroxyl-7-carboxy-1-methyl-5-vinyl-9,10-dihydrophenanthrene(9), 2-hydroxyl-7-carboxyl-1-methyl-5-vinylphenanthrene(10), luteolin(11), vanillic acid(12), daphnetin(13), p-coumaric acid(14), respectively. Compound 13 was isolated from the genus Juncus for the first time and compounds 5, 8-12 were isolated from J. setchuensis for the first time. The elevated plus-maze(EPM) was used to evaluate the anxiolytic activity of compounds 6 and 7. Compound 6 at 5 mg•kg⁻¹ and 10 mg•kg⁻¹ showed anxiolytic activity as well as compound 7 at 10 mg•kg⁻¹ and 20 mg•kg⁻¹.