Three new triterpenoids, 11,21-dioxo-2beta,3beta,15alpha-trihydroxyurs-12-ene-2-O-beta-D-glucopyranoside (1), 11,21-dioxo-3beta,15alpha,24-trihydroxyurs-12-ene-24-O-beta-D-glucopyranoside (2), and 11,21-dioxo-3beta,15alpha,24-trihydroxyolean-12-ene-24-O-beta-D-glucopyranoside (3), and two new flavonoids, apigenin-7-O-[2''-O-(5'''-O-feruloyl)-beta-D-apiofuranosyl]-beta-D-glucopyranoside (4) and chrysoeriol-7-O-[2''-O-(5'''-O-feruloyl)-beta-D-apiofuranosyl]-beta-d-glucopyranoside (5), were isolated from the whole plant of fresh celery (Apium graveolens), together with 10 known flavonoids. The structures of the new compounds were elucidated by analysis of spectroscopic data. The inhibitory effects of the compounds isolated on nitric oxide production in lipopolysaccaride-activated macrophages were evaluated.