The non-visual effects of the color temperature of fluorescent lamps were reviewed based mainly on our recent studies with special reference to physiological aspects in humans such as arousal level, autonomic nerve system including heart rate variability, blood pressure and body temperature regulation, and sleep architecture. It was concluded that there obviously existed the non-visual effects of the spectral composition of fluorescent lamps on physiological aspects, as predicted based on the functions of the nuclei located on the photic non-visual pathway.