Two new compounds, 5-methoxy-3′,4′-dihydroxy-6,7-methylenedioxy-4H-1-benzo-pyran-4-one(iriskashmirianin A) (1) and 5,3′-dihydroxy-3-(4′-β-d-glucopyranosyl)-6,7-methylenedioxy-4H-1-benzo-pyran-4-one (germanaism H) (2), along with eight known compounds (3–10), were isolated from the rhizomes of Iris germanica L. The cytotoxicities of these compounds were tested using Ehrlich's ascites carcinoma (EAC) cancer cell line by 3-(4, 5-dimethylthiazole-2-yl)-2, 5-diphenyltetrazoli-umbromide (MTT) and ATP assays. The results showed that these compounds possessed antiproliferative effects on EAC cell line. Among them, compound 1 possessed the best cytotoxic activity with IC50 ± SD of 20.9 ± 2.7 and 4.3 ± 0.9 μM for MTT and ATP assay methods, respectively.