PURPOSE: A herbicide composition that contains a combination of oxadiazon and bialaphos, thus developing sinergism to show excellent herbicidal effect on both soil and foliage treatment.

CONSTITUTION: Oxadiazon: 5-tert.-butyl-3-(2,4-dichloro-5-isopropoxyphenyl)-1,3,4- oxadiazolin-2-one, which shows high herbicidal effect against a variety of pre- emergence weeds, but scarcely against post-emergence weeds, is combined with bialaphos: 2-amino-4-methylphosphanobutyryl-alanylalanine-1-sodium salt, which is solely used to effect foliage treatment, since it has no herbicidal effect on pre-emergence weeds by soil treatment at all, at a weight ratio of 1:16W4:1. Their combination accelerates the development of foliage treatment effect without fear of increased chemical injury.