Adults' processing of own-race faces differs from that of other-race faces. The presence of an "other-race" feature (ORF) has been proposed as a mechanism underlying this specialization. We examined whether this mechanism, which was previously identified in adults and in 9-month-olds, is evident at 3.5 months. Caucasian 3.5-month-olds looked longer at a pattern containing a single Asian face among seven Caucasian faces than at a pattern containing a single Caucasian face among seven Asian faces. Homogenous and inverted face control conditions indicated that infants' preference was not driven by the majority of faces in arrays or by low-level features. Thus, 3.5-month-olds found the presence of an other-race face among own-race faces to be more salient than the reverse configuration. This asymmetry suggests sensitivity to an ORF at 3.5 months. Thus, a key mechanism of race-based processing in adults has an early onset, indicating rapid development of specialization early in life. (Contains 1 table and 2 figures.)