In today's world where public administration activities are getting more and more complex, non-judicial institutions and mechanisms that contribute to the institutionalization of good governance by protecting citizens against the administration have entered the administrative systems of many countries. Ombudsman is one of the institutions that are effective in controlling the public administration by eliminating the grievances arising from the administrative function. The success it has shown after its emergence in Sweden in modern terms has made the institution of ombudsman widespread in the world. The contribution of the Ombudsman in the establishment of good governance led to the adoption of this institution by Belgium. The question of this study is how the Belgian Federal Ombudsman affects the building and institutionalization of good governance at the federal level. Document analysis, one of the qualitative research methods, was used in the study. Legal texts and ombudsman reports directly related to the study question were examined and content analysis was carried out. The importance of the study is that it does not only examine the functioning of the federal ombudsman through legislation, but reveals how it applies the principles of good governance to its decisions.