The phytoactivity of chloroform extracts from Celosia argenteas Linn. root was measured by bioassay on testees including Oryza sativa L., Nicotiana tabacum L., Bidens pilosa L., Eclipta prostrate L., Ludwigia prostrata Roxb., Leptochloa chinensis (Linn.) Nees and antifungal activity on Sclerotinia sclerotiovum (Lib.) de Bary, Alternaria solani Jones et Grout.,Fusarium graminearum Schw., Dothiorella gregaria Sacc. was also measured. The results suggested that the extracts did not significantly inhibit the seed germination of O.sativa at 250~4 000 μg/mL, but significantly inhibited seed germination of L.prostrata, seedling root length ofN.tabacum, E.prostrate, L.prostrata, and seedling height of O.sativa, B.pilosa. Otyer relative other traits of these six plants were significantly inhibited only over 250 μg/mL. The extracts did not significantly inhibit the growth of F.graminearum at 250~4 000 μg/mL, but significantly inhibited the growth of A.solani with an inhibition rate from 23.63% to 61.01%.The growth of S.sclerotiovum and D.gregaria was significantly inhibited only over 1 000 μg/mL. It could be concluded that chloroform extracts from C. argenteas root had the potential to be developed as biopesticides.