The goal of this study is to analyze the interrelated direct and indirect impacts of urban development intensity (UDI) characteristics on carbon dioxide (CO 2 ) emissions in Korea. The study also compares the main arguments and analysis results of previous studies on cities that are effective in reducing CO 2 emissions. To do this, factors attributable to the UDI characteristics of Korea were selected, and CO 2 emissions were calculated. Then, the impact of UDI characteristics on CO 2 emissions was analyzed using the partial least squares structural equation model. The main results show that the physical, spatial, and socio-demographic characteristics of UDI have a direct impact on CO 2 emissions, and physical, economic, and city-type characteristics indirectly affect CO 2 emissions. As a result, we reach the following conclusions: (i) dense urban forms reduce CO 2 emissions; (ii) economic characteristics of UDI have impact on total CO 2 emissions, having both negative and positive effects; and (iii) medium and small cities have higher per capita CO 2 emissions than do large cities. communication infrastructure on CO 2 emissions. Land use patterns and density elements represent spatial characteristics, and transportation and communication infrastructure facilities exhibit physical characteristics. Similarly, Guerin et al. [8] found that factors such as age, gender, and education level, which indicate social and economic characteristics, such as income and house ownership, affect energy consumption. Brownstone and Golob [9] found that spatial characteristics, such as residential density, affect vehicle mileage and fuel consumption. Tate et al. [10] and Mendes [11] developed the UDI index based on physical characteristics, such as land coverage and infrastructure, and socio-demographic characteristics, such as census block group.However, as pointed out by Wang et al [7], virtually no studies comprehensively address the UDI characteristics relevant to urban planning. For example, Newman and Kenworthy [6] argued that physical factors, such as transportation-related automobiles and transportation facilities, accelerate CO 2 , but their research fails to include economic factors, such as price or income changes. Similarly, Talbi [12] studied the relationship between CO 2 and economic aspects, such as GDP, fuel consumption, fuel ratio, and energy efficiency, and found that the latter two are important for CO 2 emissions. However, this author did not consider the fact that energy consumption patterns or CO 2 emissions may vary due to other factors, such as age or city type. Schipper et al. [13] and Guerin, Yust and Coopet [8] considered socio-demographic and economic characteristics but limited their study of energy consumption to the residential sector. Similarly, Fragkias et al. [14] examined the relationship between city size and CO 2 emissions based on population, but they did not sufficiently address other characteristics influencing this relationship.Though previous studies do not comprehensively address UDI charac...