This chapter examines the extensive involvement of the Brazilian armed forces, especially the Army, in the national COVID-19 response and its implications for civil-military relations. Building on a history of domestic civic-social actions (ACISO) and law-and-order operations (GLO), the military under President Jair Bolsonaro’s administration assumed a central role in pandemic management. Military personnel were mobilized to undertake tasks such as border control, disinfection, logistical support for medical supplies and vaccines, and public awareness campaigns. While the military’s professional approach garnered some public approval for its humanitarian efforts, the chapter reveals a deeper “militarization” of public health, where military officials held key decision-making roles, often aligning with Bolsonaro’s controversial directives that diverged from international health guidelines. This politicization led to widespread criticism, allegations of mismanagement, and even corruption investigations, reportedly uncovering irregularities in health budgets. The case highlights how military involvement in civilian functions can both enhance operational coordination and expose the institution to political controversy and public distrust.