Disclosures of the present invention describe a human body-friendly light source constituted by at least one lighting unit and a plurality of color temperature (CT) reducing films stacked to each other. The CT reducing films are connected to a light emission surface of the lighting unit, so as to apply a color temperature reducing treatment to a light emitted from the lighting unit. Exponential data have proved that, two or more stacked CT reducing films exhibit an apparent color temperature reducing effect on the light. Exponential data have proved that, with the increasing of the stack numbers of the CT reducing films, the light is concerted to an orange-white light with color temperature in a range of 1,000-2,500 K, so as to make a sensitivity of melatonin suppression in response to the light be getting lower.