Cruzeiro do Sul is a municipality located in the west of the Brazilian state of Acre. Its population is 73, 948 and its area is 7,925 km².
It is bordered to the north by the state of Amazonas, to the south by Peru, to the east by the municipality of Porto Walter, to the west by the municipality of Rodrigues Alves, to the northwest by the municipality of Tarauacá, and to the northwest by the municipality of Mâncio Lima.
The prinicipal economic activity of the municipality is rubber extraction. Of lesser importance is the farming of cassava, coffee and rice.