A new anthraquinone glycoside, emodin-1-O-β-gentiobioside 1, together with three known compounds, chrysophanol-1-O-β-gentiobioside 2, physcion-8-O-β-gentiobioside 3, and chrysophanol- 1-O-β-D-glucopyranosyl-(1 → 3)-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranoside 4 was isolated from the seeds of Cassia obtusifolia. Its structure was elucidated on the basis of spectroscopic evidence.