This article examines the structural and topological transformations in the Brazilian maritime network during the COVID-19 pandemic, with a focus on adaptations made to maintain the efficiency, connectivity and resilience of cargo transport in the country. In a pandemic context where global trade was impacted by restrictions and shifts in supply and demand, complex network theory was used to analyze the structure and properties of this network. The methodology is based on quantitative analysis of data from the Automatic Identification System (AIS), which monitors the routes and movements of ships between Brazilian ports in the years 2019 (pre pandemic) and 2020 (during the pandemic). Topological metrics such as centrality, modularity, the clustering coefficient, and the average path length within the network are evaluated. The results indicate significant changes, with the strengthening of regional hubs, such as the ports of Manaus and Suape, and a redistribution of cargo flows that created denser regional clusters. The analysis also reveals a decreased in network modularity and a reduction in small world characteristics, resulting in greater average distances between ports and higher time and logistical costs for long-distance routes.