The invention discloses an ultraviolet radiation intensity fluorescence difference testing method and a device. The invention adopts two visible light detectors, wherein the light accepting surface of the first visible light detector is coated with a transparent and even lamina of ultraluminescence material which emits fluorescent light with the visible light band under the irradiation of ultraviolet ray, an electrical signal generated by the first visible light detector shows the intensity sum of the fluorescent light generated by ultraviolet ray and visible light, an electrical signal generated by the second visible light detector shows the intensity of the visible light, an electrical signal showing the intensity of the ultraviolet ray is obtained by difference amplifying the two electrical signals, and the electrical signal is calculated to the ultraviolet ray intensity by a singlechip after converted by AD. The invention adopts the ultraluminescence and difference theories, can automatically remove the influence of bias light, and measures the ultraviolet ray with high accuracy.