In this article we perform an analysis of the immigration issue in the public discourse of a number of Italian political actors in the period 2018-2019. We select Twitter as a main arena of political communication, as the literature shows it has become an important part of the Italian information ecology. The novelty of our study lies in the application of the Stuctural Topic Model technique to a large corpus of tweets in order to capture their policy content. Consistently with previous studies, we show that politicians belonging to different parties emphasize different issues in their tweets. In particular, in the period under consideration the debate on immigration was monopolized by Salvini’s Lega confirming the hypothesis that immigration is generally emphasized by actors that are «issue-owners». Our results also confirm that the immigration issue is closely aligned with populist actors, as it was mostly emphasized by politicians belonging to the Lega and the 5Star Movement.