To obtain an agent for attracting and killing noxious insects such as moth and fly and free from environmental pollution without using an insecticide by dissolving a noxious insect attractant such as muscovado liquor in an aqueous solution containing a hot-water extract of seaweeds belonging e.g. to the genus Eucheuma of Rhodophyta.

This attracting and killing agent contains one or more components selected from preferably 1-5wt.% (in the stock solution of the noxious insect attracting and killing agent) of a muscovado liquor, preferably 2-5wt.% of molasses and preferably 1-3wt.% of Miso (fermented bean paste) and preferably further contains one or more fruit juice components selected from the juice of apple, pear, orange, etc. The above attractant is dissolved in an aqueous solution containing a hot-water extract of seaweeds belonging to the genus Euchema and/or Ceramium. The noxious insect attracting and killing agent 1 is filled in a bottle 6 made of a soft resin, an attractant odor dissipating port 2 and a rain-intrusion preventing eave 3 are formed on the wall above the water level and an attracting and killing agent introducing port and its lid 4 are formed on the top of the bottle to obtain the noxious insect attracting and killing apparatus.