Abstract: Herbicide acticity of new sulfonylurea herbicide NK#94827 was screened by bioassay of tap root of Brassica napus L., the results indicated that, the herbicide activity of NK#94827 was equal to that of chlorsulfuron and tribenuron-methyl. Furthere study by siol treatment in laboratory revealed that, NK#94827 possessed good herbicide activity to Acalypha australis L. and Echinochloa phyllopogon (staf) Koss. Maize growth inhibition of NK#94827 was lower than that of chlorsulfuron and tribenuron-methyl, however, it was greater than that of foramsulfuron. The results of pot bioassay in greenhouse indicated that, Triticum, aestivum L. and Oryza sativa L. were safe to NK#94827 at application dosage of 15g/hm2 and 30g/hm2 of soil treatment and foliage spraying, while phototoxicity to Glycine max, Avena sativa L. and Brassica napus L. was observed in all treatments of this study.