An image capturing device includes an image capturing unit, a light filter module, a light sensing unit, an infrared light source and a processing unit. The light filter module includes a first light filter and a second light filter. The first light filter filters an infrared and allows a visible light to pass. The second light filter filters a visible light and allows an infrared to pass. The light sensing unit senses an environmental light. When the processing unit determines that an intensity of the environmental light is higher than a threshold, the processing unit alternately switches the first light filter and the second light filter to a front of the image capturing unit, controls the image capturing unit to capture a visible light image through the first light filter, and controls the image capturing unit to capture an infrared image through the second light filter.