The indoor tests of natural immersion in NaCl solution and fast freeze thaw cycling were carried out to study the chloride ion penetration to reactive powder concrete, and the calculation method of freeze thaw impact factor kd was put forward. The results show that chloride ion diffusion coefficient of specimens after natural immersion could be calculated based on Ficks second law, and it decreases as immersion time increases. However, the chloride ion diffusion coefficient decreases at first then increases as the cycle times increase. The life prediction models were established considering freeze thaw damage, chloride ion erosion, and combined effect of freeze thaw cycling and the chloride ion erosion. Life prediction results show that reactive powder concrete has a good durability under the combined action of freeze thaw cycling and chloride ion erosion.