Cyhalofop-butyl is an oxyphenoxypropionic acid type herbicide. It is mainly used in rice seedling field, direct seeding field and transplanting field to control most malignant gramineous weeds such as barnyardgrass, Qianjin and niujin grass, and can effectively control weeds resistant to dichloroquinolinic acid, sulfonylurea and amide herbicides. It has the characteristics of high efficiency, low toxicity and low residue.