This study aimed to explore the effects of color temperatures on color task performance, and also to propose a color task implementation model to be used in future research. In the study, three attributes of color were the focus in the color differentiation task. The study was conducted with 100 participants as with-in subjects design, in a full-scale office set-up under two different color temperature; warm white light (2700K and cold white light (4000K. The speed and accuracy of the color task were examined as an indication of task performance. The mood change of participants was assessed by Watson’s Positive and Negative Affect Schedule (PANAS mood measurement, self-satisfaction was assessed by Office Lighting Survey (OLS and perceived performance was assessed by questionnaire. The results showed that the total time spent for the color tasks performances have no significant. difference between 2700K and 4000K. It also showed that total accuracy of color task performances is statistically better under 4000K, compared to 2700K. Whereas color temperatures did not affect value differentiation task performance significantly, hue and chroma differentiation tasks performance were significantly better under 4000K color temperature. In terms of the effects of color temperature on mood, it is found that 4000K color temperature affected participants mood in a positive way. Also, self-satisfaction and perceived performances of participants are significantly better under 4000K color temperature.