PROBLEM TO BE SOLVED: To obtain a sterilizing device of making temperature in an inner part of a sterilization container uniform and sterilizing an object to be sterilized at a uniform temperature.SOLUTION: In the sterilizing device wherein trays 6 on each of which the objects 5 to be sterilized are mounted are stack in multi-stage and housed in a closed sterilization container 4 and mediums such of hot water, steam, cooling water and the like are sprayed toward the inner parts of the trays from spray nozzles 7 attached to spray tubes 8, the spray tubes are disposed on left and right sides of the trays to be positioned in an intermediate points in the rear and the front direction of the trays along the vertical direction of the trays, and a front end side spray nozzles 7a whose spray angle is set so as to spray an area from a nearly intermediate part in the front and the rear direction of the trays beyond a lateral side 16a on a front end side of the trays as a spray range and a rear end side spray nozzles 7b whose spray angle is set so as to spray an area from a nearly intermediate part in the front and the rear direction of the trays beyond a lateral side 16b on a rear end side of the trays as a spray range are provided at the spray tube 8a and the spray tube 8b of the right and the left spray tubes 8a and 8b, respectively, in nearly center positions in height directions of space parts formed between trays stacked in multi-stage.
