The ability to distinguish between members of one's own species has greatly assisted the evolution of sociality in mammals, leading to individualized relationships and cooperative networks. Because kin selection is important for the evolution of complex societies, other advantages must derive from the ability to distinguish kin from non-kin1. Taking advantage of the chimpanzee's face-recognition abilities and computer skills2,3, we presented five subjects with the task of matching digitized portraits of unfamiliar females with their offspring. We find that chimpanzees can match the faces of mothers and sons, but not mothers and daughters, providing evidence for a mechanism of kin recognition in primates that is independent of previous experience with the individuals in question.