Connected to the Federal University of Rio de Janeiro, the museum has expositions that include anthropology, archaeology and paleontology, among others.
The vice director of the museum, Luiz Fernando Dias Duarte, told Globo news the museum suffered chronic underfunding.
"Everybody wants to be supportive now. We never had adequate support," he said.
On Instagram, Rio Mayor Marcelo Crivella called on the country to rebuild.
"It's a national obligation to reconstruct it from the ashes, recompose every eternal detail of the paintings and photos. Even if they are not original, they continue to be a reminder of the royal family that gave us independence, the (Portuguese) empire and the first constitution and national unity," he said.
AP
