This paper analyses the relationship between institutional quality and green innovation in Italian regions (NUTS2). We examine how varying levels of institutional quality influence the regional capacity to generate green innovation, disentangling the effects related to economic institutions (corruption, government effectiveness, and regulatory quality) from the impacts associated with political institutions (rule of law and voice and accountability). Using a panel of data for 2004–2018 on green patents, we use an instrumental variable IV approach to control for endogeneity and several robustness checks. Our results show that the most important drivers of green innovation are related to the quality of political institutions. These findings remain robust, even when checking for economic and environmental controls, demonstrating that green innovation is more related to political decisions and social capital than innovation in general is.