Due to worsening environmental conditions around the globe, firms have been investing a great deal of money in green technologies as a way of coping with the environmental crisis. This paper uses a unique data set based on the Korea Innovation Survey to examine the impact of green innovation on labor productivity, and the determinants of environmental activities in 2010. The empirical results show that green innovation intended for both firm and customer benefits has a positive effect on labor productivity. This finding means that firms need to implement firm-oriented green innovation as well as customer-oriented green innovation in order to increase their performance. Our findings also show that there are significant differences in aggregate green innovations depending on different firm sizes and industries. Specifically, large firms implement environmental activities more than small ones, and pollution-intensive industries tend to invest more in activities related to environmental technology.