The amount of forest removed was up by nearly double compared to April last year, it showed.
Environmental campaigners claimed deforestation had become “institutionalised” in the country which contains much of the world’s largest tropical rainforest and pointed the finger at Brazil’s president for the record levels.
Deforestation in the Brazilian Amazon totalled 1,012.5 sq km in all but the last day of April, according to data from national space research agency Inpe, who has been reporting monthly tallies since 2015/2016.
Data for 30 April will be released next week. But the figures already show deforestation to be at the highest level on record for April.
It comes after records were also broken in January and February this year.
“The April number is very scary. Due to the rain, it is traditionally a month with less deforestation,” Suely Araujo, from Climate Observatory, said.
Marcio Astrini, the head of the same Brazilian environmental advocacy group, said: “The cause of this record has a first and last name: Jair Messias Bolsonaro.”
Deforestation in the Amazon has accelerated since the right-wing president took office three years ago and weakened environmental protection.
He argues more farming and mining in the rainforest – which is an important carbon sink and one of the planet’s richest areas of biodiversity – will help to reduce poverty.
But the Amazon is one of the planet’s richest areas of biodiversity, as well as an enormous carbon sink that is considered key to fighting against the climate crisis.
Trees, especially in old-growth forests, play an important role in removing planet-warming carbon dioxide from the atmosphere.
Bill McGuire, a climate hazards professor at University College London, said the level of deforestation in the Brazilian Amazon last month was “appalling news”.
“To say we’ll miss it when it’s gone, is like saying we’ll miss our lungs when they’re gone,” he tweeted.
Ane Alencar, science director of the Amazon Environmental Research Institute (IPAM), said the amount of rainforest cleared was “absurd”.
“It seems that the clearing of forests has become institutionalized in the country as something common, with record after record,” she said.
Researchers have also found the Amazon rainforest is losing its ability to bounce back from extreme events, raising concerns it is racing towards “tipping point”.
Scientists fear this could trigger a mass dieback of trees and the forest turning into a savanna.
The Brazilian government said it was making major efforts to fight environmental crimes and authorities were cooperating to combat deforestation in five Amazon states.
Additional reporting by agencies