To effectively eliminate odor after evacuation in a flush toilet by using a small amount of chemicals.

The toilet deodorizing aromatic device stores an aromatic agent or a deodorizing agent and forcedly sprays the aromatic agent or the deodorizing agent to the outside by chemical spray mechanism. The toilet deodorizing aromatic device takes in water flowing from a water receiving port 5 to a flush water tank and guides it to a water flow detection part 12, and the water flow detection part detects the water supply to the flush toilet. A fan drive circuit is activated when detecting the water supply to the flush toilet and the chemical spray mechanism is activated, so that chemical spraying is automatically carried out and the chemical for spraying is effectively used during water supply to the flush water tank in a manner conforming to draining timing of the flush toilet.