Protected areas (PAs) are vital for the conservation of Brazil's biodiversity (Barber et al.2014). However, they are at risk of a downgrade in legal status due to economic pressures on natural resources (Bernard et al.2014; De Marques & Perez 2014; Pack et al.2016). Mining is one of the most urgent environmental threats in Brazil (Ferreira et al.2014; El Bizri et al.2016), with plans in place for a 10-fold increase in the number of mining projects in c. 8 years. If all were developed, the Brazilian territory occupied by mining would increase 23-fold in the near future. Currently, 12 697 projects covering 98 × 10⁵ ha are planned within PAs. Licensing and exploitation of 53% of this land will depend on the approval of three bills that intend to authorize mining in areas where it was formerly forbidden. Here, we analyse the potential consequences of the approval of these new policies for conservation.