Traffic system controls the material flow of modern society and it shapes the spatial distribution of socio-economic system by providing logistics service. Its change has significant impact on the spatial organization of socio-economic system. Here we report an investigation on the impact of traffic change on spatial mobility at different scales, and based on the theory of kinetic energy and potential energy transformation in physics, a method of measuring the mobility of a single city is constructed. On both macro and micro scales, we selected 285 municipalities (major cities with districts and with Ganzhou as a typical case) to investigate the impact of traffic change on spatial mobility based on the spatial analysis of electronic map data and statistical data collected in 2005, 2010 and 2015 with the aid of ArcGIS. Our results find that traffic change has significant impact on the spatial mobility of municipalities at different scales. Our conclusions can be drawn as follows. First, traffic flow is the most dominant reflection of spatial mobility, and by interacting with other factors of time, space and distance, a special spatial organization, flowing space, is formed. Second, the influence of traffic on spatial mobility is different from scale to scale. On macro scale, traffic change will generate new inter-regional flow space. The degree of interdependence increases as spatial mobility increases; on micro scale, traffic change will change the spatial organization within a city where the material flow of the city will change accordingly. Finally, the land transport network density of municipalities in China was in a gradient distribution. Central cities and cities with the most variable traffic flow have the greatest spatial mobility. Traffic change has an obvious positive driving force on the mobility of municipalities (cities with districts), and it plays a more significant leading role in the migration and dispersal of population in urban areas, and the extension and direction migration of functional zones.