Abstract: Identifying and zoning semiconductor industry agglomerations are foundational and pioneering tasks for the national planning layout and high-quality development of this industry. This study, based on headquarters-branch investment relationship data of 15 757 Chinese semiconductor enterprises in 2022, uses complex network graph segmentation techniques such as location quotient, minimum spanning tree, and modularity to construct a semiconductor industry network, covering 256 prefecture-level cities in China (excluding Chinese Hong Kong, Macao, and Taiwan). The study reveals that: 1) the spatial distribution pattern of China’s semiconductor industry is predominantly concentrated, with a non-uniform development trend of higher levels in the east and south compared to the west and north; 2) the overall outwards investment network exhibits a geographical distribution resembling a diamond structure and rhombus pattern. Local investment agglomeration areas differ significantly between the east and west, with the east having a dual-core or multi-core traction type and the west displaying a single-core traction type; 3) among the six major agglomeration areas, the Yangtze River Delta (YRD) has the highest level of regional integration. The Pearl River Delta (PRD) shows strong internal connections but significant polarisation on its east bank of PRD. The Beijing-Tianjin-Hebei (BTH) urban agglomeration exhibits a gradient-driven dual-core structure, whereas the Shandong Peninsula urban agglomeration relying on the eastern Shandong metropolitan area and western Shandong metropolitan area forms horizontal connections. Dual-core growth pole agglomeration patterns are observed in the Guanzhong Plain urban agglomeration and Chengdu-Chongqing urban agglomeration; 4) ultimately, the spatial agglomeration area of China’s semiconductor industry can be divided into four primary zones (the southern zone of China, the eastern zone of China, the northern zone of China, the western zone of China) and 20 secondary zones. The results can be directly applied to national and regional industrial planning, particularly for defining development priorities, optimizing interregional division of labor, and reducing spatial fragmentation in China’s semiconductor industry.