Disclosed is a herbicidal composition comprising flazasulfuron, or its salt (compound A) and at least one benzonitrile compound selected from the group consisting of chlorthiamid and dichlobenil, or its salt (compound B), wherein the mixing ratio of compound A to compound B is from 1:80 to 1:240 by weight ratio. Also disclosed is a method for controlling undesired plants (such as perennial cyperaceae in lawns) or inhibiting their growth, which comprises applying a herbicidally effective amount of the following compound A and a herbicidally effective amount of the following compound B to the undesired plants or to a place where they grow: Compound A: flazasulfuron, or its salt, Compound B: at least one benzonitrile compound selected from the group consisting of chlorthiamid and dichlobenil, or its salt wherein the dose of compound A is from 10 to 50 g/ha, and the dose of compound B is from 800 to 6,000 g/ha.
