In a comparative laboratory study the effects of lighting on human well-being and performance have been studied compared for LED and fluorescent lamps. Two different lighting scenarios (static and dynamic lighting) were implemented and evaluated for both light sources each. 28 subjects between 20 and 59 years (16 m, 12 f, 30 +/- 11) spent one day for each light source in the laboratory, the lighting scenario being constant within the subject. They were tested on well-being, concentration and performance as well as had their heart-rate-variability measured. The results show that the LED lighting was rated more interesting, colorful, comfortable, warm, inviting and beautiful than fluorescent lighting (evaluation, p = 0.004) as well as more casual, private and pleasant than fluorescent lighting (p = 0.058). No significant differences have been found between LED lighting and fluorescent lighting concerning well-being, performance and concentration. The HRV-parameters show no significant effects during the test day for the light source and the lighting situation, while the interaction shows significant effects. During the night following the test day significant effects can be seen: The night after fluorescent lighting shows higher heart rates and respiratory rates and variability is significantly lower than during the night after LED lighting.