Provided is a cell treatment apparatus that includes: an isolator; a disposal box that includes a storage part; and a decontamination unit, wherein the disposal box includes: a first opening and closing device that is configured to allow the isolator and the storage part to be communicated with each other at the time of disposal of the waste product and allow them to be shut off from each other after the putting-in of the waste product and before the disposal of the same; and a second opening and closing device that is configured to allow the storage part and the outside to be communicated with each other at the time of disposal of the waste product, which has been put into the storage part, and allow them to be shut off from each other after the disposal of the waste product.