PURPOSE: A herbicide that is prepared by adding a carrier showing basicity when suspended in water to 0,0-diphenyl-S-(2-methylpiperidin-1-yl)carbonylmethyl phosphorodithioate as the effective component, thus having high stability and high selective herbicidal activity for rice.

CONSTITUTION: In a herbicidal composition comprising a mineral carrier supporting 0,0-diphenyl-S-(2-methylpiperidin-1-yl)carbonylmethyl phosphorodithioate as the effective component, a carrier showing basicity when suspended in water, e.g., a basic hydrated silica, bentonite or talc is used. As a wetting agent, a basic hydrated silica with large oil-absorbing power is preferred and the amount to be added is generally 10W30% and, when it is particulate or finely pulverized, 5W50% is preferred in any basic carrier.