This article explains about feminist advocacy and gender regime in the European Union which could reform gender inequality into high level of gender equality. The European Union have had gender inequality index ways lower than the average of world’s gender inequality index. As per sectors—such as in economy, education, politic, and health—gender equality index in the European Union also keep becoming more and more gender equal between women and men. These evoke a question, why does the the European Union could achieve high level of gender equality? The aim of this article is to understand the reasons behind the high level of gender equality in the European Union. Theory of Advocacy and International Regime theory are used in this article to analyze the reasons behind the problem above. This article uses qualitative approach, data collective, and data analysis method to gradually solving the problem being brought in this article. As the result, this article shows that feminist advocacy and gender regime are the reasons behind the significant increase of gender equality index so that the European Union could achieve high level of gender equality in the world.