Xambioá is a municipality in the state of Pará, in the North Region of Brazil. It lies in the eastern part of the state, on the left bank of the Araguaia River, directly across from the town of Araguaína in Tocantins. The river forms the boundary between Pará and Tocantins at this point, and the two states are connected in the area by a bridge over the Araguaia.
The name Xambioá is also associated with an Indigenous people, the Xambioá or Karajá do Norte, who live in Tocantins. The group numbered about 1,350 people at the end of the 19th century, then suffered a severe and violent population decline that left only 40 people in 1959. Their population has since begun to recover slowly, reaching 268 people in recent counts.
The municipality is located in a region of the Amazon biome, and its economy and settlement patterns are tied to the Araguaia River and to road connections linking Pará with Tocantins and the rest of northern Brazil.