The Ka'apor capuchin has been described as having one of the smallest geographical ranges of any other
Cebus species in the Amazon. They can be found in the eastern border of the Brazilian Amazon along the Atlantic coast; more specifically in the states of
Pará and
Maranhão. The region is known as for having the highest population density in all of the Amazon. Due to the large human population living in the same area, the species tend to live in isolated patches of tall, lowland terra firme forest. Included in their range, are two protected stretches of land: the
Gurupi Biological Reserve and the Lago de Turucuí Environmental Protection Area. Studies of the Ka'apor capuchin populations in these areas have had very varying results but the consensus seems to be that the species is quite rare, even within their known range. In one study, researchers following a group of
C. kaapori observed that their average daily travel was of approximately 2,175 m and utilized most quadrants of their home range every month. == Behavior ==