A new phenolic glycoside 1 and three known compounds (2–4) have been isolated from the 95% ethanolic extract of Eucommia ulmoides Oliv. leaves. Their structures were identified as erythro-1-O-methyl-2-O-β-D-glucopyranosyl-guaiacylglycerol (1), 3,5-dimethoxybenzyl alcohol 4-O-β-D-glucopyranoside (2), salidroside (3), and dihydroconiferin (4) from spectroscopic data (1H NMR, 13C NMR, HSQC, and HMBC) and using chemical methods. In the in vitro assay, compound 1 displayed potent inhibitory activity against aldose reductase with an IC50 value of 7.82 μM. [ABSTRACT FROM AUTHOR]