Forty thousand people signed a petition organised by the charity Survival.
Now markers are being put in the forest to prevent people from harming the land.
Threats to the tribe
The tribe has only been known to people in the outside world for 30 years.
The tribe lives off the land, gathering and hunting food without harming the environment.
Stop harming the forest
The tribe are hopeful they will be able to continue living in their part of the forest in peace.
Meanwhile the Brazilian government must make sure outsiders don't ignore the order.
Go to the link on the right to find out more on Survival.