From 1964 to 1983, as a large-scale construction activity of national defense, science and technology, industry and transportation infrastructure with the goal of war readiness, was rapidly launched in the hinterland of China, the development and evolution of the Third-line Construction (“Third-line construction” refers to a large-scale national defense, science and technology, industrial and transportation infrastructure construction activity guided by war preparedness carried out in 13 provinces and autonomous regions in the central and western regions of China from 1964 to 1983, and its development and evolution promoted the development and rise of modern industry in Sichuan, and profoundly affected the formation and evolution of urban pattern and urbanization process in Sichuan.) promoted the development and rise of modern industry in Sichuan, and profoundly affected the formation and evolution of urban pattern and urbanization process in Sichuan. Under the unified planning and deployment of the central government, most of the Third-line Construction projects in Sichuan were distributed along the main railway lines and rivers, and an industrial agglomeration belt with Guangyuan, Jiangyou, Mianyang and Deyang as the main nodes was gradually formed in the north of Sichuan. By analyzing the characteristics of Third-line Construction planning layout and the spatial form composition of the remaining factories in the north of Sichuan, the paper tries to explore the influencing factors of the layout of Third-line industrial plants in the north of Sichuan. In addition, a large number of Third-line industrial remains are used inefficiently or even abandoned, and the value of the precious Third-line industrial remains is at risk of loss and vanishing. How to better excavate, protect and inherit the value of Third-line industrial remains is the key concern of the study of Third-line Construction. This paper introduces the relevant theoretical methods of urban morphology, and summarizes and analyzes the distribution, composition and characteristics of the building communities in the factory area by combing the spatial organization form and functional structure of the industrial relics of the third-line construction in the four cities in northern Sichuan. On the basis of the current situation of a large number of third-line construction remains, the composition and evolution of the factory space were discussed, and the influencing factors and their impact on the later urban planning and social and economic development were explored, so as to enrich the research on the planning layout and protection and utilization of the third-line construction industrial remains.