Assuming that change of national spatial structure impacts on regional transportation demand, this study examines the relationship between urban dispersion and transportation energy consumption. Although previous studies verified that transportation energy consumption per person is lower in the cities with higher population density, studies which deal with quantitative analysis about the relationship between urban dispersion and transportation energy saving are not found. For the analysis, several factors are used, such as entropy, degree of urban dispersion, urbanization ratio, population density, and land size of region. Findings show that indicators of urban dispersion are closely related to trip volume. Unlike the cases of developed countries, larger urban dispersion is expected to generate more trips between cities. This study first suggests that economically and culturally self-sufficient cities should be developed to minimize regional trips. Second, integrated studies of transportation and land use should be expanded from urban to national level. Finally, discussions of transportation energy saving should include not only urban but also rural areas.