Abstract: Identifying the evolution of spatial structure is of great significance in promoting regional high-quality development and synergistic development. Based on the perspective of "relationship", we investigated the evolution of the network structure of urban links in the Yangtze River Delta (YRD) region from 2015 to 2022 in terms of "flow-direction-flow-point characteristics-community structure". The influencing factors were explored using the modified gravitational model and the method of social network analysis. The results showed that: ①The pattern of the strength of urban spatial links had changed from "one big, three small" to "multiple blossoms"; The first link in the region formed a spatially multi-centered and relatively closed territorial system, and the direction of the first link did not have a clear trend of concentration. ② From the perspective of the overall characteristics of the YRD region, the spatial connection between cities had increased. The spatial structure was solid, and the two-way interaction was strong; From the perspective of the individual characteristics, the degree of urban centrality had changed from unbalanced to balanced, and the network had gradually flattened. ③In 2015-2019, the core area undertook the radiation-driven function in the region, and there were more cities in the role of "brokers";  In 2019-2022, the "broker" segment disappeared, and the former core region changed to a "two-way spillover" role. ④Geographic proximity had a stable positive effect on the association network, and the level of market environment and scientific and technological innovation had also shown a positive spillover in recent years; The level of economy showed a stable negative significant effect, and the level of information infrastructure showed a negative significant effect in recent years; The administrative relationship was no longer obvious, which indicated that cities were breaking down the boundaries of the provinces to create associations.