The foundations of Aalto University Student Union lie in the student unions of Helsinki School of Economics, University of Art and Design Helsinki and Helsinki University of Technology. When these three universities merged on the first of January 2010 to form Aalto University, the student unions merged as well and formed the new Aalto University Student Union (AYY).

The unification of the student unions was planned for years before it actually happened. The first Representative Council Elections of AYY were held 22.-24.4.2009 and the term of the Council elected then will last until the elections of 2011. The first elections saw vibrant campaigning and 450 students stood as candidates. The turnout was also record breaking in student union elections: on average, 35 percent of voters cast their vote.

In the fall of 2009 an executive group, comparable to the Student Union Board, was established to prepare the forming of AYY. The most important projects of the executive group were preparing the budget and plan of action, creating insignia, organizing a recruitment campaign for Board applicants and hiring a financial director.