The tourism industry in Europe is growing rapidly especially from 2017 to 2019. The increasing number of tourist arrivals has negative impacts on tourism, such as overtourism. The phenomenon occurs when there are too many visitors in certain tourism destinations and impacted the quality of life in the area. Overtourism has negative impacts such as environmental damage, damage to cultural sites, economic inequality, and damage to life quality of the local community. This paper aims to analyze the phenomenon that currently raising in European Union member states. The focus of this paper is EU’s role in handling overtourism that occurring in Venice, Barcelona, and Santorini as the cities mentioned are located in EU’s member states. This research is a qualitative study, with case study of overtourism occuring in Venice, Barcelona, and Santorini. The theme is analyzed using formal intergovernmental organization and compliance theories. It is found that European Union’s role in handling overtourism in Venice, Barcelona, and Santorini is by applying their regulations in environmental, tourism, and sustainability fields to the mentioned countries because EU is a supranational intergovernmental institution and their member states have to comply every regulations made by EU.