The purpose of the present invention is to solve issues with conventional hyperthermia treatment for cancer. The present invention provides a cell activation device that is capable of suppressing the progress of cancer and contributing to the irradiation of cancer cells. This cell activation device (100) activates the gene restoration mechanism naturally hound in cells and supports cancer treatment, by cutting infrared rays having a wavelength greater than 7.5 µm at which said rays works as heat rays and irradiating infrared rays having a wavelength which equals to or is smaller than 7.5 µm on an affected area containing cancer cells. An infrared irradiation therapy using wave length of no more than 7.5 µm is a gentle therapy that activates a latent function of human cells, such as activates the gene restoration mechanism. If a type that irradiates infrared rays without contact with the patient is used, cells can be activated while the patient is leading their normal life and without restricting physical freedom.
