Abstract: With the development of 6G communication technology, the Space-Air-Ground Integrated Network (SAGIN) demonstrates tremendous potential in areas such as emergency communications, environmental monitoring, and intelligent transportation. However, SAGIN's heterogeneous structure, high link dynamics, and widely distributed resources pose significant challenges to efficient network management and optimization. The rapid development and application of artificial intelligence (AI) technology in communication networks in recent years has provided new opportunities for the intelligent evolution of SAGIN. This article first systematically introduces the basic components and key features of the SAGIN network architecture, and summarizes the technical principles and adaptability advantages of current mainstream AI technologies. Secondly, this article deeply explores the application and recent progress of AI in typical SAGIN scenarios, including intelligent resource management, mobility management, aerial platform path planning, routing and link selection optimization, network slicing and resource orchestration, and task offloading and computational collaboration. Finally, this article summarizes the challenges faced by applying AI technology in SAGIN networks and outlines future directions for the integrated development of AI and SAGIN. This article summarizes the advantages and progress of AI technology in SAGIN networks, aiming to provide a technical reference for the research and application development of AI-enabled SAGIN.