This paper discusses the relationships between regional differences of citizens' awareness and social capital for climate change policies. Nowadays greenhouse gas emissions for households and the service sector are especially increasing in Japan. Therefore raising citizens' awareness of climate change policies is necessary at the regional level. This study focuses on social capital (SC) which shows regional qualities. It is also known as an indicator that affects regional policy performance. The definition of SC in this paper is based on Putnam (1993), “SC refers to features of social organization, such as trust, norms, and networks that can improve the efficiency of society by facilitating coordinated actions.” “The public opinion polls for climate change policy” by the Japanese cabinet office was used as the indicator of citizens' awareness. The relationship between citizens' awareness and SC was analyzed based on the Principal Components Analysis. Moreover, how the results of this analysis affect a low carbon society was analyzed by the Data Envelopment Analysis. As a result the awareness factors that were affected by SC and regional characteristics were clear. Finally, it was recognized that we should consider possible uses of SC according to regions and sectors for climate change policies. JEL Classification: Q54, R00