In order to establish the quantitative model of temperature action in natural climate environment, the law of temperature change in natural climate environment, the lag characteristics of temperature response of micro environment inside concrete and the method to establish the temperature action spectrum in natural climate environment were explored first. Then the influence of sunlight exposure on the temperature of concrete surface was studied. Finally, the revised method to obtain temperature action spectrum in natural climate environment under unsheltered condition was put forward, and its feasibility was verified through an example of the prediction of temperature response of micro environment inside concrete in natural climate environment under unsheltered condition. The results show that the temperature of concrete surface is basically higher than air temperature under the action of sunlight. The diurnal temperature range（Rm） can be used as an indicator of sunlight intensity, and the temperature increase of concrete surface increases linearly with the increase of Rm. The prediction accuracy of temperature response of micro environment inside concrete in natural climate environment under unsheltered condition is improved when the revised action spectrum of environmental temperature is used, so the revised method is feasible.