This paper uses multinational panel data of 26 countries during 19982010 to analyze the influence of the change of domestic income difference and domestic income distribution in different countries on carbon dioxide emission quantity, i.e., the influence of the factors such as their per capita GDP, population density, the proportion of industry to GDP, Gini Coefficient and cross term of income distribution on carbon dioxide emission quantity. Empirical analysis results show that income distribution has significant impact on carbon dioxide emission, that there is a negative relation between Gini coefficient and carbon dioxide emission but the negative relation reduces with GDP increase and that there is a positive relation between per capita GDP and cross term of income distribution and carbon dioxide emission. Thus, the relation between economic development and carbon dioxide emission can be more completely described if income unhomogeneity is considered. 