Structural health monitoring (SHM) takes a breakthrough of civil engineering by integrating electrical, magnetic, photic, acoustic, thermal and other physical variables, chemical variables, information technology, computer science and technology as well as communication technology into a civil structure to make the structure have self-sensing and self-diagnostic abilities. The SHM is also a basis of smart earth, which may take a profound impact on the behavior and lifestyle of society. The SHM includes sensing technology, data acquisition, transmission and management, and health diagnosis. In this paper, the sensing technologies are developed for monitoring of fatigue, corrosion, score and seismic damages by using integrating piezo-electric ceramic array with optical fiber Bragg Grating sensor array and ultrasonic monitoring technology. The approaches of health diagnosis for civil structures have been proposed by authors and their group. The damage detection approaches considering the uncertainties of civil structures and environmental factors are proposed, such as probabilistic damage identification approach based on dynamic sensitivity analysis and damage detection approach by using information fusion techniques. A multi-scale finite element model (FEM) updating approach is presented for conducting safety evaluation. The modeling approaches for various loads and responses using SHM data are proposed and the framework of SHM-based structure safety evaluation is established. Finally, the role of SHM in developing smart earth in the future is also put forwarded.