To provide an insect-catching device having good catching efficiency by preventing an insect once entered into the interior from easily escaping to the exterior, facilitating the disposal treatment of the caught insect, making the insects gathered about a light unremarkable, and preventing rain water, or the like, invaded into the case from remaining in the interior.

This insect-catching device for catching the insect by attracting the insect has an insect-catching case having a space in the interior, an attracting light for attracting the insect into the interior of the insect-catching case, the insect-introducing entrance from which the light of the attracting light is emitted and through which the insect is introduced into the interior of the insect-catching case, an insect-blocking means for preventing the insect entered into the interior of the insect-catching case from the insect-introducing entrance from escaping to the exterior of the insect-catching case, an insect-gathering part installed so as to be detachable and for gathering the dead bodies of the insects, an introducing opening of the gathering part for introducing the insect entered into the interior of the insect-catching case to the insect-gathering part, and an insect-blocking means for preventing the insect entered into the interior of the insect-gathering part from escaping to the exterior of the insect-gathering part.