Under the general backgrounds of fast development of economy, China' power industry is undergoing a new upsurge of infrastructure construction. With the urgent need of the whole society for reliable power supply, Condition Based Maintenance strategy is becoming the mainstream of the operation and management of the power system. In this paper, recent progress of Condition Monitoring and Diagnostic technologies for major power apparatus are reviewed. Also, some statistical data on practical on-line monitoring applications in China are introduced. At last, the key problems and trends of CMD are discussed with a viewpoint future perspective.