The spread of disinformation on social media platforms has in the last few years gained much scholarly attention, in particular its ability to alter democratic processes. The focus of this thesis has however been on the discourse surrounding disinformation rather than disinformation itself, more precisely, the construction and perception of disinformation as a security threat. Disinformation is an issue which is rapidly evolving with the creation of new technologies and opportunities. The aim of this thesis has been to investigate if this has led to a shift in the perception of disinformation as a threat and therefore a change of policy for the EU. This was realised through the utilisation of Carol Bacchi's WPR approach toolkits, in combination with the foundational principles derived from securitization theory. The thesis shows that the EU’s perception of disinformation as a threat has evolved from mainly focus on the decline of public trust and democratic processes. To also include and recognise a more multifaced view of the issue with a larger focus on manipulation, technology driven threats and media literacy deficiency.