Abstract: To investigate the temperature effect of the mass concrete on the subway station bottom slab after pouring, based on the mass concrete bottom slab pouring project of Huaxing Street Station of Chengdu Metro Line 19, the dry shrinkage and self-shrinkage characteristics of concrete caused by hydration heat reaction were discussed by field monitoring and numerical analysis method. Using the finite element analysis software, the temperature field was applied to simulate the strain variation characteristics of the concrete bottom plate by stratification and subsection. The main factors on the deformation of mass concrete bottom plate were analyzed, and the reasonable control measures were proposed based on the construction characteristics and construction period of the subway station. The results show that there are great differences in temperature and strain of each layer of mass concrete floor. When the pouring days are 0-3.0 d, the main influencing factors on floor deformation are the dry shrinkage and the self-shrinkage of concrete after intense hydration reaction. When the pouring days are 4.0-10.0 d, the main influencing factors are the temperature and the temperature difference effect caused by the uneven heat dissipation of concrete.