Calcium-magnesium-alumino-silicate (CMAS) corrosion is one of the most critical failure mechanisms of thermal barrier coating (TBC). CMAS attack significantly alters the temperature and stress fields in TBCs, resulting in their delamination or spallation. In this work, the dynamic evolution process of suspension plasma sprayed (SPS) TBC under CMAS attack is investigated. The CMAS corrosion leads to the formation of reaction layer and subsequent bending of TBC. Based on the observations, a corrosion model is proposed to describe the generation and evolution of the reaction layer and bending of TBC. Then, numerical simulations are performed to investigate the corrosion process of free-standing TBC and the complete TBC system under CMAS attack, respectively. Results show that the CMAS corrosion has a significant influence on the stress field, such as the peak stress, while it has little influence on the steady state temperature field. It should be noted that the peak of stress increases with holding time which increases the risk of the rupture of TBC. There is a parabolic relationship between the stress and reaction layer thickness in the holding stage. Furthermore, in the traditional failure zone, such as the interface of top coat and bond coat, the stress obviously change during CMAS corrosion.