A fluid handling apparatus 10 has a plurality of fluid handling subassemblies 16 arrayed on a plate body 12. Each of the fluid handling subassemblies includes: an injecting section 26 for injecting a fluid; a fluidized section 28 for allowing the fluid to continuously flow downwards; a fluid housing chamber 30 for receiving the fluid from the fluidized section; a wall portion 20 formed between the fluid housing chamber and the fluidized section; slits 20b for allowing the fluid to enter the fluid housing chamber; and a surface-area increasing means 22 for increasing the area of a contact surface with the fluid in the fluidized section. The slits extend from a lower end positioned in the vicinity of the lower end of the fluidized section, to an upper end higher than the upper end of the fluidized section, for allowing the injecting section and fluidized section to be communicated with the fluid housing chamber.