A fine particle diffusion device includes: a first outlet (10a to 10c) through which a first air current is discharged to a space above a living space within a living room； a second outlet (10d) which is arranged below the first outlet (10a to 10c) and through which a second air current is discharged to a space below the first air current； and a fine particle generation device (17) which generates fine particles. Here, the fine particles generated by the fine particle generation device (17) are discharged into the living room, and the concentration of the fine particles discharged through the first outlet (10a to 10c) is lower than the concentration of the fine particles discharged through the second outlet (10d).
