The purpose of this study was to examine the relationship between corporate social responsibility and internationalization. The companies executed the CSR activity using the published index of economic justice (KEJI index) surveyed from 2013 to 2014. A total of 286 companies were included in the study. Results are as follows. First, the degree of internationalization groups showed significant differences. It found that the higher the proportion of international companies showed positively CSR activities. Especially, It found that environmental management and customer protection showed positively performed. Second, environmental management and customer protection showed positive effect on firm internationalization. It found that the higher the proportion of international companies thought environmental management and customer protection activity were more important. This study proposed that CSR activity are very important in firm performance. It showed CSR activities and strategy are presented for sustainable management.