•A thermal stress stiffening method for rotating disk vibration suppression.•Dynamics of rotating flexible disk system heated at disk inner boundary.•Thermal deformation of flexible disk system with initial transverse runout.•Experiment verification of the proposed method for vibration suppression. A thermal stress stiffening method for the vibration suppression of a rotating flexible disk with initial transverse runout is investigated via theoretical and experimental methods in this paper. This method generates in-plane thermal stress by heating the disk inner boundary, thereby enhancing the transversal bending stiffness of the disk and suppressing the transverse vibration. The thermal stress stiffening's influence on the natural frequency, dynamic stability and steady-state response of the disk with and without a mass-spring-damper system loaded is analyzed by theoretical computation. Via a finite element method software, it is found that thermal expansion could change the non-flat disk's shape. A specialized testing set is designed, and the content of the theoretical analysis is tested through experiments. The experimental results show that this method is not only suitable for a freely rotating disk, but also for the vibration suppression of a flexible disk loaded with a transversely symmetrical mass-spring-damper system, and even for that of a flexible disk loaded with a single-sided one. Moreover, this method is easy-to-use and cost-effective in practical applications as a simple and effective way for the vibration suppression of rotating disks. Display omitted