An electronic device capable of detecting ultraviolent radiation and a method thereof are provided. The device includes a camera, a voltage-sensitive optical medium, a control switch, and a processor. When the electronic device enters an ultraviolent radiation detecting mode, the camera captures a first image. The processor controls the control switch to create an electrical potential across the optical medium and cause it to become darker after the camera captures the first image. The camera captures a second image after the control switch has allowed an electrical potential for a first preset time interval. The processor acquires reads the respective brightness of the first image and the second image, determines any difference, and determines and outputs the level of intensity of the ultraviolent radiation intensity by reference to a table of differences.