In 2016, regulations on energy clusters were introduced into Polish law. Since then, the Ministry of Energy has conducted two rounds of calls, in which it has awarded sixty-six certificates for outstanding pilot energy clusters. According to the assumptions of the Polish government, by 2030 about 300 energy clusters and energy cooperatives are to be created in Poland. However, currently energy clusters are developing slowly, and many of those which have been created in recent years are not operating well. Cluster members blame unclear, unstable, and unspecific law for the lack of development. In this context, the aim of this article is to identify the most important legal barriers to the development of energy clusters in Poland.