Abstract The paper aims to discusses the conception of the right to the city put into practice in urban-environmental projects and in the discourse and practice of the diverse institutions’ agents of the justice system in Brazilian Amazon, particularly in the city of Belém, Pará state. The paper central question is: what are the conceptions of right to the city followed by the justice system agents that act administratively and judicially in large urban macro-drainage interventions in the city of Belém, Pará state? Methodologically the study is based on the case study method and on exploratory and qualitative approach. The public agents interviewed are those who routinely act in cases involving the macro-drainage projects of the Una, Tucunduba and Estrada Nova basins and they are linked to the following organizations: Pará State Public Prosecution Service (MPE), Pará State Public Defender (DPE), Brazilian Lawyers Association - Pará state section (OAB), Pará State Attorney's Office (PGE) and Pará State Court of Justice (TJE). The main conclusion is that the exercise of the right to the city is inside the political system and that the legal system acts in the conflicts mediation that arise in political disputes and in the conceptions of development that emerge in the city.