Three new triterpenoid saponins, named celosin E (1), celosin F (2) and celosin G (3), together with a known compound cristatain (4), were isolated from the seeds of Celosia argentea L. (Amaranthaceae). All the isolated compounds were obtained for the first time from this plant. The structures of new compounds were characterized on the basis of extensive NMR experiments and mass spectrometry data. The antitumor and anti-inflammatory activities of the four compounds were tested in vitro.