The authors synthesized a series of novel 5-heterocycloxy-3-substituted-1-（3-trifluoromethyl）phenyl-1H- pyrazole derivatives. Herbicidal activities of the two intermediate compounds and thirteen target compounds were evaluated via Brassica napus and Echinochloa crusgalli（L.） Beauv tests. Bioassay results show that some of the compounds exhibit better inhibiting activities against Brassica napus and some of the compounds exhibit bleaching activities against Echinochloa crusgalli（L.） Beauv at 100 μg/mL.
