In order to solve the problems of poor effects in operation and maintenance training for smart substation, a simulation system of operation and maintenance based on augmented reality technology is introduced and implemented. Firstly, the differences between augmented reality (AR) and virtual reality (VR) are compared, and the design framework of operation and maintenance simulation system based on AR technology is proposed. Then, the 3D model base of each equipment scenario in substation is established by data preprocessing, hierarchical pattern recognition and image shape retrieval. The key technologies such as three-dimensional registration and tracking technology, virtual-real fusion technology and human-computer interaction are further introduced in smart substation. Finally, the above key technologies are integrated into the operation and maintenance simulation platform for smart substation. Practical training examples demonstrate that based on augmented reality technology and virtual reality scenario to simulate the operation, maintenance and repair of intelligent substation, a more realistic immersive virtual training environment is constructed for substation operation and maintenance personnel from both visual and tactile aspects, and the simulation effect is more realistic, effective and practical.