Downpours that started late Monday have wreaked havoc across parts of the cities of Juiz de Fora and Uba, about 310km north of Rio de Janeiro. Throughout the week, rescuers have been assisting victims and recovering bodies.
Minas Gerais' fire department said five people are missing, while more than 5500 people have been forced to leave their homes.
President Luiz Inácio Lula da Silva will visit the devastated region on Saturday to meet with local leaders, according to a statement from the presidential palace.
The government has authorised the release of around 3.4 million reais ($A930,318) for reconstruction efforts and humanitarian assistance.
Nearly a quarter of Juiz de Fora's population - around 540,000 people - live in places that have been identified as being at risk of natural hazards related to land and water, according to a 2023 report by Cemaden, a Brazilian government agency that monitors natural disasters.
Brazil's meteorology institute, Inmet, warned of a "great danger" of more bad weather in parts of Minas Gerais as well as other Brazilian states, including Rio and Sao Paulo. Those areas are all at risk of landslides, river overflows and major flooding, forecasters said.
Footage from Thursday evening showed torrents of brown water flowing through tourist hot spot and old colonial town Paraty, also in southeastern Brazil. Authorities told residents to avoid flooded areas and hillsides and to avoid sheltering under trees due to a risk of lightning strikes.
Scientists say extreme weather is happening more frequently due to human-caused climate change.
Major flooding in Brazil's southern Rio Grande do Sul state in May 2024 led to the deaths of at least 185 people and ravaged nearly everything needed for economic activity, from shops to factories, farms and ranches. Financial losses were above 10 billion reais.
Greenpeace Brazil on Instagram called for actions that prepare cities for climate change and ensure protection for vulnerable populations.
"Avoiding tragedies like the ones currently happening in cities in Minas Gerais and other states needs to be a priority," the nonprofit said. "Disasters are also the result of political choices."