Leonardo DiCaprio's environmental organisation is putting $5m (£4.1m) towards helping the Amazon rainforest after the recent surge in fires there.
Earth Alliance will give the money to local groups and indigenous communities as they work to protect the Amazon.
The National Institute for Space Research in Brazil says there have been more than 72,000 fires in the Amazon rainforest this year.
That's up from 40,000 at the same point last year.
A statement on the Earth Alliance website says: "The destruction of the Amazon rainforest is rapidly releasing carbon dioxide into the atmosphere, destroying an ecosystem that absorbs millions of tonnes of carbon emissions every year and is one of the planet's best defences against the climate crisis."
The organisations receiving the cash are Instituto Associacao Floresta Protegida (Kayapo), Coordination of the Indigenous Organizations of the Brazilian Amazon (COIAB), Instituto Kabu (Kayapo), Instituto Raoni (Kayapo) and Instituto Socioambiental (ISA).
The surge in forest fires has been put down to a rise in deliberate deforestation for cattle farming.
Brazil's President Jair Bolsonaro has been accused by critics of encouraging the destruction of the Amazon through a lack of action on environmental issues.
But he says non-governmental organisations (NGOs) - like charities - could be to blame for starting the record number of fires. He hasn't offered any evidence for this claim.
Earth Alliance was founded by Leo and two other philanthropists in July - aiming to protect wildlife, push for climate justice and secure indigenous rights.
The Amazon Forest Fund is the group's initiative to raise money for the protection of this specific area.
In an Instagram post on Saturday, the actor said he is "deeply concerned about the ongoing crisis in the Amazon, which highlights the delicate balance of climate, biodiversity, and the wellbeing of indigenous peoples".
View this post on Instagram
#Regram #RG @earthalliance #EarthAlliance, launched in July by @LeonardoDiCaprio, Laurene Powell Jobs, and Brian Sheth, has formed an emergency Amazon Forest Fund with a commitment of $5 million dollars to focus critical resources for indigenous communities and other local partners working to protect the life-sustaining biodiversity of the Amazon against the surge of fires currently burning across the region. Join Us. 100 percent of your donation will go to partners who are working on the ground to protect the Amazon. Earth Alliance is committed to helping protect the natural world. We are deeply concerned about the ongoing crisis in the Amazon, which highlights the delicate balance of climate, biodiversity, and the wellbeing of indigenous peoples. To learn more or to donate, please visit ealliance.org/amazonfund (see link in bio) Photos: @chamiltonjames, @danielbeltraphoto 2017
He wants the public to get involved and support the crisis too, linking to ways people can make donations.
Meanwhile, international leaders at the G7 summit in Biarritz, France, are reportedly reaching an agreement on international help towards the crisis.
UK Prime Minister Boris Johnson said Britain would provide £10m to protect the Amazon rainforest.