Abstract: As China's energy structure continues to undergo transformation and the energy revolution deepens, integrated energy services have become an effective approach to enhancing energy efficiency and promoting green development. Intelligent operation and maintenance services are crucial means to implement the concept of integrated energy services, achieving safe, intelligent, and efficient energy use. The characteristics of intelligent operation and maintenance of integrated energy systems (IES-IOM) are analyzed, and its development process are elaborated through three stages: manual operation and maintenance, automated operation and maintenance, and intelligent operation and maintenance. Based on the data of IES-IOM, key core technologies for intelligent operation and maintenance are proposed. An IES-IOM service business system is constructed, including the establishment of operation and maintenance knowledge base, equipment condition assessment, equipment condition prediction, equipment fault diagnosis, and operation and maintenance strategy recommendation. By focusing on two typical scenarios of integrated energy systems, namely commercial buildings and industrial parks, the application effects of intelligent operation and maintenance service business are analyzed. Finally, the challenges faced by IES-IOM are addressed, and future development directions are proposed, aiming to provide theoretical support for a deeper understanding and promotion of IES-IOM development.