In the context of Brazil-Paraguay historical relations, the construction of the Itaipu hydroelectric dam on the Paraná River – in the border between the two countries – was one of the most important initiatives (in political, economic and energy terms). The events between Brazil and Paraguay involving the Itaipu project are part of South America's geopolitics. In this sense, the present article will focuses the negotiations that preceded and continued throughout the construction of the plant and the treaties and main events and agreements that established the criteria for the operation of the hydroelectric power plant. The Itaipu Treaty, signed in 1973, provides for the revision of financial clauses by 2023. The present work aims to examine the relations between Brazil and Paraguay throughout history and analyze the impacts of the Itaipu Dam on these relationships. This article is a qualitative research, from the perspective of International Relations and Political Geography, enriched with cartography created by the authors with Arc GIS software.En el contexto de las relaciones históricas entre Brasil y Paraguay, la construcción de la central hidroeléctrica de Itaipú Binacional, en el río Paraná – enla frontera entre los dos países – fue una de las iniciativas más importantes (en términos políticos, económicos y energéticos). Los eventos entre Brasil yParaguay relacionados con el proyecto de Itaipú son parte de la geopolítica de América del Sur. En este sentido, el presente artículo enfocará losprincipales eventos y negociaciones que precedieron y continuaron a lo largo de la construcción de la central hidroeléctrica y los tratados y conveniosque establecieron los criterios para su operación. El Acuerdo de Itaipú, firmado en 1973, prevé la revisión de las cláusulas financieras para el año 2023.En este sentido, el presente trabajo tiene como objetivo examinar las relaciones entre Brasil y Paraguay y analizar los impactos de Itaipú Binacionalsobre ellas. Se trata de una investigación cualitativa, desde la perspectiva de las Relaciones Internacionales y de la Geografía Política, enriquecida concartografía creada por los autores con el software Arc GIS.In the context of Brazil-Paraguay historical relations, the construction of the Itaipu hydroelectric dam on the Paraná River – on the border between the two countries – was one of the most important initiatives (in political, economic and energy terms). The events between Brazil and Paraguay involving the Itaipu project are part of South America's geopolitics. In this sense, the present article will focus on the negotiations that preceded and continued throughout the construction of the plant and the treaties and main events and agreements that established the criteria for the operation of the hydroelectric power plant. The Itaipu Treaty, signed in 1973, provides for the revision of financial clauses by 2023. Thus, the present work aims to examine the relations between Brazil and Paraguay throughout history and analyze the impacts of the Itaipu Dam on this relationship. This article is qualitative research, from the perspective of International Relations and Political Geography, enriched with cartography created by the authors with Arc GIS software.