[目的]明确5%丙草胺·硝磺草酮颗粒剂对水稻移栽田鸭舌草的防效和对水稻的安全性。[方法]在水稻移栽后5d进行了田间药效试验。[结果]5%丙草胺·硝磺草酮颗粒剂在推荐剂量下防效达到100%,而且对水稻安全,但是制剂量30000g/hm~2的高剂量对水稻不安全。[结论]5%丙草胺·硝磺草酮颗粒剂可以有效防除水稻田鸭舌草,建议其作为水稻土壤封闭处理用,在鸭舌草3~4叶前进行单独均匀或毒土撒施。 [Objective] The research aimed to clarify the control effect of 5% pretilachlor mesotrione on the transplanted Monochamus alternatus and its safety to rice. [Method] The field efficacy test was conducted 5 days after rice transplanting. [Result] The 5% pretilachlor mesotrione granules had 100% control effect at the recommended dosage and was safe for rice. However, the high dosage of 30000 g / hm -2 was not safe to rice. [Conclusion] 5% pretilachlor mesotrione granules could effectively control Monochamus alternatus in paddy field. It is suggested that it should be used as rice soil sealing treatment, and should be applied separately or poisoned before 3 ~ 4 leaves of monocotyledon .