Nine compounds were isolated and purified from the ethyl acetate fraction of Apium graveolens L. roots by silica gel and Sephadex LH-20 column chromatographies. Their chemical structures were identified on the basis of their physical and chemical properties. These isolated compounds were elucidated as palmitic acid (1),cinnamaldehyde (2),naringenin (3),Isoscopoletin (4),xanthotoxin (5),6-methyl -5,7-dihydroxyPhthalide (6),2-phenylethyl-O-β-D-glucopyranoside (7),apigenin-7-O-β-D-glucopyranoside (8) and salidroside (9). Compounds 3,4,6,7 and 9 were isolated from this plant for the first time. All isolated compounds were evaluated in vitro by MTT assay against human liver cancer cell line BEL-7402,human gastric cancer cell line SGC-7901 and human lung cancer cell A549. Compound 4 showed cytotoxic effect against A549.