[PERSON] (2009) predicted the dynamic modulus of concrete with the measured surface wave velocity. The calculated dynamic modulus was in good accordance with the measured results through the resonance method. [PERSON] (1963) proposed the TG (Trtnik Gregor) parameter for the strength gain prediction, which is the peak value ratio between the high frequency and low frequency range of the transmission signal in the frequency domain. The TG parameter was found to be strongly linearly correlated to the strength gain during the first eight hours. The TG parameter also became stable after the first several curing hours; thus, it cannot be used for the strength gain prediction during the early stages (1-28 days). The ultrasonic pulse velocity (UPV) has also been used to monitor the hardening behavior. The UPV-based models were found to be especially suitable for the early age property prediction [PERSON] (1966). The influence of the air void structure on the concrete properties has already been widely studied [PERSON] (1966), but the study on the influence of the air void structure evolution of concrete performance is relatively limited. [PERSON] (1966) studied the influence of entrained air voids on the concrete transport ability. It is reported that the entrained air void can decrease or increase the concrete transport ability, depending on saturation level. [PERSON] (1966) studied the strength loss due to the entrained air bubbles in concrete. The compressive strength was found to decrease, with [PERSON] (1966) analyzing the effect of air void clustering on concrete strength loss. It is found that the strength loss was mainly caused by the total air content, rather than the air void clustering; this is contradictory to the findings of [PERSON] [27]. Currently, research on how the transport ability is evaluated during curing age is limited, and the effect of air void clustering on compressive strength is still not clear. This paper aims to monitor the air void structure evolution and the change of concrete properties during the early-age and hardened stages. Three concrete samples with the same mix design but different air entrainment agent dosages were prepared. The ultrasonic scattering measurements were conducted during early-age and hardened stages to detect the air void structure evolution. The experimental attenuation was obtained based on the wave spectral ratio of the first and the second transmission waves in the frequency domain. The method is following the former study [15] on hardened concrete samples by employing the combination of normal and log-normal distribution. The theoretical attenuation was then calculated with the obstacle scattering theory, by integrating the pre-determined cement paste, aggregate attenuation, and air void distribution effects. The inverse analyses were conducted to determine air void distribution parameters by achieving the minimum error between theoretical and experimental attenuations. The ultrasonic measured air void distribution was then verified with the ASTM C 457 [11] test results at Day 28. The influence of air void structure evolution on concrete properties were also evaluated in this study, including transport ability, compressive strength, and dynamic modulus. The transport ability was evaluated with the electrical resistivity measurement. The experimental measurements on compressive strength and ultrasonic parameters were fitted with linear relations at early stages. The dynamic modulus predicted with ultrasonic parameters was also compared with ASTM C 215 measurement of hardened concrete.