This cross-country study statistically investigates the determinants of environmental orientation of entrepreneurial activity. It builds on a new institutional theory framework and uses data gathered in the course of the Global Entrepreneurship Monitor to examine the institutional impacts and individual characteristics which influence the degree of environmental orientation of entrepreneurial activity, using a multilevel analysis. Our key findings are threefold: First, the results indicate that environmental orientation is frequently used as a source for securing legitimacy of entrepreneurial ventures. Second, we find lower degrees of environmental orientation among more educated entrepreneurs. Third, for many variables, such as age, gender and income, differences are observed when compared to earlier findings on the determinants of social entrepreneurship. Policy makers can learn from the analysis that policy measures should not only be designed specifically for environmental entrepreneurship, but also be adapted to the domestic economic circumstances, as, for example, environmental taxes only show significant effects on environmental orientation of entrepreneurial ventures in OECD countries. From a practitioner’s perspective, this indicates that a lack of regulation can provide opportunities for environmentally oriented entrepreneurial ideas.