To evaluate the effect of early freeze on service performance of concrete, the frost environment for early age concrete was simulated. Macro property parameters such as the compressive strength, splitting tensile strength, dynamic elastic modulus, and micro indexes such as pore structure and water absorption characteristics during service period of early frozen concrete were tested. The effects of frost environmental parameters, such as the frost onset time, frost temperatures and frost durations, on the service performance of early frozen concrete and damage mechanisms were analyzed. Results show that accompanied by the decreasing frost temperature and the increasing frost duration, the deterioration of macro properties of early frozen concrete during service and the paste to air ratio increases, whereas the air content, the water absorption after immersion and volume of permeable pore space decrease. Moreover, the greater bubble amount under different pore diameters is observed. The performance degraded significantly with the frost temperature decreased from -1℃ to -5℃ or the frost duration increased from 2h to 4h, but only slightly with the further decreasing frost temperature from -5℃ to -9℃ or the further increasing frost duration from 4h to 8h. For the early frozen specimens with different frost onset times, the degradation in service performance caused by freezing between the initial setting and final setting time is the most severe, followed by that before the initial setting time, and decreases gradually with increasing frost onset time after the final setting time. With the delaying frost onset time,the paste to air ratio increases whereas the water absorption after immersion and volume of permeable pore space decrease gradually. The bubble amount under different pore diameters of concrete frozen before the final setting is greater than that after the final setting.