At the beginning of the seventies started the so-called "cascade of responsibility" which initiated the founding of numerous mechanisms of transitional justice, one of which is the International Criminal Tribunal for the former Yugoslavia, which was established on 25 May 1993. The problem is, however, that according to the public pools and researches (IDEA, Documenta, Belgrade Humanitarian Law Centar) the ICTY very early on started to lose its social legitimacy, which is in international law defined as the beliefs of "those addressed" and their capacity to facilitate compliance with international law. The paper examines reasons behind the lack of social legitimacy of the Tribunal in Croatia, which is examined in the work of the Tribunal itself (work of the Chief Prosecutor’s Office, work of the judges, the late establishment of the Outreach Office, and series of “diplomatic” mistakes), on level of international politics (the establishing the Tribunal, broadly set objectives, insufficient influence on the recognition of judgments in the former Yugoslavia), and finally, on the level of national politics in Croatia (influences of political parties and the media). The paper explains the importance of social legitimacy for mechanisms of transitional justice, and the consequences of the lack of such legitimacy for the Hague Tribunal - the fulfillment of the mandate, the cooperation with the countries of former Yugoslavia, and finally on the overall process of the transitional justice.