Man new towns are established in China with the intention of providing desirable places to live. Nevertheless, these new towns often lack the flourishing street life, small businesses, and variety of social activities that old towns have to offer. This paper explores the spatial reasons why old towns tend to perform socio-economically better than new towns by adopting Space Syntax, Spacematrix, and Mixed Use Index (MXI) through geographical information system (GIS). These three analytical tools are first applied separately and then combined within the GIS matrix to compare Chinese new and old towns in terms of degree of spatial network configuration, building density, and degree of land use mix. The included case study will utilize the example of Songjiang, Shanghai, which features both a distinctive old town and new town section. Songjiang Old Town features more urban areas with a high-level of spatial values from the perspective of street network configuration, building density, and land use mix as compared to its new town. These high spatial value urban areas promote a vital city centre, the type of which is absent from the new town. Meanwhile, Songjiang New Town’s problems are caused by a lack of well-integrated main roads and local streets, a low degree of interaction between buildings and streets, and low degree of land use mix as well. Certain spatial principles explaining how the neighbourhood unit is poorly designed in accordance with current planning and urban design practice are identified in this article. Alternative spatial indicators for aggregating areas with a high degree of urbanity are proposed for avoiding these flaws in future practice.