Based on Fick's second law of diffusion, the chloride diffusion equation in reinforced concrete (RC) pipe pile was developed considering the effects of environment temperature and chloride binding. The experimental study on the effect of environment temperature on chloride diffusion in RC pipe pile was conducted in this paper. RC pipe piles with different water-to-cement (w/c) ratios (0.30, 0.45 and 0.55) were exposed to 5% chloride salt spray for 32 days at different exposure temperatures (21, 30, 50℃). Based on the experimental results and proposed model, the chloride concentration profiles, surface chloride concentration, apparent and effective diffusion coefficients, activation energy and binding capacity values of RC pipe piles with different w/c ratios at different exposure temperatures were explored. The experimental results show that the free chloride concentration, surface chloride concentration, apparent and effective diffusion coefficients increase with the environment temperature. The binding capacity increases significantly with the increase of environment temperature from 21 to 30℃. However, the binding capacity decreases slightly when the environment temperature increases from 30 to 50℃. It could be concluded that the chloride diffusion into RC pipe pile follows the Arrhenius theory due to the linear distribution of the log-variation of apparent diffusion coefficient with the inverse of absolute temperature.