Although geographically distant, China has increased its presence in the South Atlantic in recent years and is now a relevant actor in the region for the first time in history. This phenomenon is part of the general trend of increasing maritimisation of Chinese foreign policy, which dates back to the late 1990s and deepened with the launch of the 21st Century Maritime Silk Road in 2013. This initiative, which seeks to increase China’s international maritime clout, already involves several South Atlantic countries, both on the American and African continents. This move by China into the South Atlantic has already received some academic attention (Abdenur & Souza Neto, 2013; Pereira & Duarte, 2023), but still little is known about the specific geopolitical and technological implications for Brazil, which, although not formally associated with the Chinese initiative, is the most relevant country in the region. Thus, the chapter aims to examine this growing Chinese presence in the South Atlantic, focusing the analysis on three maritime areas: ports, maritime transport, and energy. For each of them, the interests and strategies that structure Chinese actions will be assessed as well as their geopolitical and technological impacts on Brazil. It is argued that, given the asymmetry of power between Brazil and China, there is a risk that Chinese interests will prevail in the South Atlantic, increasing Brazil’s technological dependence and accentuating the country’s geopolitical vulnerabilities. This implies the need for Brazil to define an effective strategy for its relationship with China.