Architectural color has been analyzed from humanistic, aesthetic and other qualitative aspects rather than a scientific quantitative perspective. In order to obtain the function relation that different color temperature of daylights influence architectural color and to make architectural color design more scientific, typical daylight and correlation theories have been analyzed. Meanwhile an experiment research of daylight color temperature and color rendering properties while making typical daylights D65 and D55 as standard illuminants has been carried out. The results indicate that in sunny day the daylight color temperature changes quickly in the morning and evening, and it remains stable from sunrise to 3 hours before sunset(4300K~5300K). And there is a distinct direct proportion relation between color differences and color temperature differences of daylights, the proportional coefficient is 0.01, and the function relation is ΔE=1.0×10 -2×ΔK (3 500