Abstract: Plants of Sedum lineare were treated with PEG-6000 at concentrations of 5%, 10%, 20%, or 30% to simulate drought stress, or without PEG-6000 treatment (control). The fresh and dry weights, water content, root dehydrogenase activity, and contents of inorganic matter, organic matter, inorganic osmotica, and organic osmotica of S. lineare were determined. Seven organic acids were determinated by high-performance liquid chromatography. Compared with the control, under PEG-6000 treatment, fresh and dry weights, water content, root dehydrogenase activity, contents of inorganic matter, Na⁺, K⁺, and NO₃^- decreased, but those of organic matter, free amino acid, proline, and soluble sugar increased, while soluble protein content initially increased and then decreased. HPLC showed that the change rates of seven organic acids differed from each other. Comprehensive analysis indicated that the simulated drought stress inhibited the growth of S. lineare, and the inhibitory effect became stronger with the increase in PEG-6000 concentration. Under the simulated drought stress, S. lineare did not accumulate inorganic osmotica (Na⁺, K⁺, NO₃^-), but used organic osmotica (such as free amino acids, proline, soluble sugar, soluble protein, oxalic acid and propane diacid) for osmotic adjustment.