[Problem] To provide a chemical agent volatizer with which it is possible to use up all of a chemical agent in a container, even in cases in which rod-shaped volatizer elements are used. [Solution] The present invention is provided with: a container having an internal space enclosed by a bottom wall and a peripheral wall, having an opening at the top, and containing a liquid chemical agent within the internal space； and a plurality of rod-shaped volatizer elements which are inserted into the internal space from the opening such that one end protrudes from the opening. The container is constituted such that a straight line connecting the peripheral edge of the inner wall surface of the bottom wall, and the inner peripheral edge of the opening, is situated in the internal space, and the bottom wall has a protrusion protruding towards the center from the peripheral edge of the inner wall surface of the bottom wall.本發明之課題，係在提供一種藥劑揮散器，即使是使用棒狀揮散體時，也可將容器內之藥劑全部用盡。本發明，具有：由底壁部及周壁部所圍繞之內部空間，而且，在上部具有開口，前述內部空間用以收容液狀之藥劑的容器；及以其中一端部從前述開口突出之方式，從前述開口被插入前述內部空間的複數棒狀揮散體；前述容器，係以連結前述底壁部之內壁面的周緣及前述開口之內周緣的直線，位在前述內部空間之方式來構成，前述底壁部，係具有從該底壁部之內壁面的周緣朝中央隆起之隆起部。
