The utility model provides a detection device of cell phototoxicity experiments, which comprises a lightproof experimental chamber. The top of the experimental chamber is provided with a plurality of ultraviolet A (UVA) irradiation light sources with single wavelength as 365nm. A plurality of cell culture solution cavities capable of fixing membrane plates are arranged in the experimental chamber, and an ultraviolet quartz window protects the membrane plates from the outside environment and enables the membrane plates to be lighted by the UVA irradiation light sources. A warm culture chamber is connected with a warm culture controller and a cell culture solution supply device which are required by cells for life. An ultraviolet and ozone sterilizer, a ventilating device and a humiture controller are arranged in the experimental chamber to enable the experimental environment to meet the requirement. An irradiation light probe detects the intensity of the UVA irradiation light sources and is controlled by a computer, and experimental parameters can be stored in the connected computer or printed through a printer. The detection device has the advantage of being widely used for scientific research on phototoxicity in the fields of chemistry industry, toxicological health, environmental protection, labor and job danger prevention, medical science and the like.