Damages in a structure alter its static and dynamic characteristics. These changes occur in some structural parameters such as the mass, the stiffness, the flexibility and the damping matrices of the structure and can be characterized by changes in the modal parameters, i.e., modal frequencies, modal damping values and mode shapes, and their derivatives, such as the modal curvature and modal stress energy. According to the properties of cable-stayed bridges, various damage indexes of static and dynamic are constructed to indicate damage of cable, tower and girder respectively. A comprehensive index accounting for their interaction and the whole bridge damage is presented which is robust to measurement noises and uncertainties in ambient conditions. The sensitivities of these damage indexes are illustrated by numerical studies. The effectiveness of the proposed damage detection method of cable-stayed bridges is demonstrated through an engineering project.