The Serra dos Reis State Park is divided between the municipalities of Costa Marques (91.17%) and São Francisco do Guaporé (8.83%) in Rondônia.

[4] On 22 January 2013 the governor decreed the creation of the park with an area of about 42,286.9376 hectares (104,493.298 acres) in the municipality of Costa Marques, under the Secretariat of State for Environmental Development (SEDAM).

[7] In January 2011 the Rondônia Public Ministry said it would investigate the illegal removal of 517 cubic metres (18,300 cu ft) of logs, or about 17 truckloads, from the area around the state park.

[8] In January 2016 SEDAM announced findings of illegal activity in the previous quarter in nine units that benefited from ARPA in the state.

In the Rio Cautário State Extractive Reserve and the Serra dos Reis State Park they had seized a motorcycle, a tractor and six trucks loaded with 695 cubic metres (24,500 cu ft) of logs and 105 cubic metres (3,700 cu ft) of sawed timber, 930 wooden stakes and various camping and fishing items.