Abstract: Under the combined influence of linear urban form and the digital economy, the evolution of commercial centers follows a spatial restructuring path that differs from that of conventional clustered and radial urban forms. Taking Lanzhou, a typical linear city in Northwest China, as an example, this study uses POI data and questionnaire survey data from 2013 to 2023 to construct a commercial center vitality index. It characterizes the evolution of spatial patterns and changes in consumer behavior in three major commercial centers, namely Xiguan Cross, Xizhan Cross, and Tieluju Cross, and identifies their main driving factors based on the Mantel test and the XGBoost model. The results show that: 1) under the linear spatial constraints along the main corridor of the Yellow River, Lanzhou’s commercial centers exhibit structural differentiation characterized by “core stability–node upgrading–peripheral decline,” and new comprehensive commercial growth poles have gradually formed around emerging transportation hubs; 2) population agglomeration, public transport accessibility, and consumption capacity are key driving forces behind the evolution of commercial centers in linear cities, showing significant nonlinear and threshold effects across different types of business districts; 3) online consumption does not simply replace physical consumption. Instead, it promotes the functional upgrading of mature business districts and accelerates the functional reorientation of marginal business districts by changing consumption frequency and the combination of business formats. Based on these findings, this study proposes a hierarchical and differentiated governance framework for commercial centers in linear cities. It suggests strengthening the high-intensity agglomeration function of comprehensive nodes along the main corridor, guiding the transformation of old business districts toward community-based and daily-life service functions, controlling the expansion of new large-scale commercial supply in weaker urban segments, and incorporating commercial vitality monitoring into the refined governance of existing urban spaces. This study provides empirical support for embedding intelligent technologies such as GeoAI into urban commercial space planning, and offers references for optimizing commercial layouts and enhancing urban development resilience in other linear or terrain-constrained cities.