PROBLEM TO BE SOLVED: To provide a noxious insect-exterminating agent capable of appropriately exterminating the noxious insects for individual vegetation, exterminating flying noxious insects in the vicinity of above the ground, and also exterminating the noxious insects eating the surface or inside of the vegetation and the insects living in a soil or larvae of other generation of the noxious insects by one effort. SOLUTION: This ring state sheet type noxious insect-exterminating agent is provided by forming ring state sheets made from a resin as a path surrounding the ground part of an objective plant for extermination along the ground surface, and holding a vaporizable insecticidal component and a non-vaporizable insecticidal component in the resin forming the ring state sheets in a dispersed state. As the ring state sheets, one ends of many strips of paper type sheets are joined to form the resin sheets, the strips are opened as a fan shape for forming a ring by closing both ends of a comb teeth state joined materials, and also fixing tools 3 for joining both opposing end edges are installed at that time.
