Abstract: This paper presents a three-dimensional finite element model for simulation of the temperature field and its variation during the construction of Longkaikou RCC dam, with a full consideration of major factors: hydration heat of cement, cooling effect of water pipes, variable ambient temperature, and reservoir level. The simulation results demonstrate that the calculations of temperature are in good agreement with in-situ measurements. According to our prediction, a large zone of high temperature 28-30 ?C occurs in the dam layer between elevations EL1230-1260 m and it will gradually shrink after completion of dam construction through heat exchange with air and reservoir water; the mean temperature in the dam will be lowered asymptotically to a range of 20-22 ?C in ten years and remain there afterward. The temperature distribution patterns were found to depend much on the local dry-hot climate conditions in the valley and the effect of water cooling measures.