The application of intelligent engine room systems in the field of ship automation is becoming increasingly important. This review focuses on the research of engine room fault diagnosis in ships, proposes the technical system of intelligent engine room systems, and discusses the research content of engine room condition monitoring technology and fault diagnosis technology. The paper points out that industrial intelligence is one of the main directions of industrial technological development, and emphasizes the intelligent transformation in the design and manufacturing of intelligent ships. The paper further introduces the engine room as the core of a ship, and emphasizes the importance of its operational efficiency for overall performance. However, most of the current domestic ship engine room automation systems are closed and isolated, unable to upload engine room equipment data in real time, and cannot meet the requirements of ship classification societies. Therefore, fully sensing the status of engine room equipment and using big data analysis and intelligent diagnostic technology to improve engine room operational efficiency become the future development direction.