Autogenous volume deformation is an important parameter of anti-cracking behaviors of concrete. The sensitivity analysis of influence of concrete autogenous volume deformation on thermal stress of Xiaowan high arch dam is carried out based on simulation of temperature field. When presuming autogenous volume deformation, expansion concrete and shrinkage concrete are considered. The results show that early expansion and early shrinkage concretes have obvious influence on arch dam’s early thermal st ress; however have less influence on dam center’s maximum thermal stress. The longer of expansion period, the smaller of dam center’s maximum thermal stress; and the final residual thermal stress, which can benefit the concrete’s anti-cracking quality.