|A fundamental study was conducted to develop a thermal stress analysis method that can reproduce the temperature and deformation behavior of massive precast concrete subjected to steam curing. First, experiments were conducted on specimens manufactured using steam curing. Next, thermal stress analysis using finite element method was performed on these experiments to study the concrete temperature, strain behavior, and crack index. It was confirmed that the concrete temperature and strain behavior up to demolding were consistent with the experimental results. As for the cracking index, it was confirmed that the time when the crack index reached its minimum differed depending on the thickness of the specimen and the ambient temperature.