The Orange-eared Tanager (Chlorochrysa calliparea) occurs from southern Colombia to northern Bolivia between 900 and 2,000 m elevation. We describe for the first time the nest of the genus Chlorochrysa, based on five nests of C. calliparea, and provide information on incubation and nestling growth from August through December 2009 and 2010 in Manu National Park, Cusco, Peru. The Orange-eared Tanager has a distinct and unique nest location in clumps of moss hanging from horizontal branches, previously unknown among tanagers. The nest structure, however, was similar to that of most tanagers. We observed use of a nest-like structure as a dormitory, not previously reported for the Thraupidae. Clutch size was one egg and the nestling period was 21 days. The female made an average of 8.8 foraging trips/day from the nest which lasted on average 33.1 min with nest attentiveness of 58.9%. The small clutch suggests close affinity with mountain tanagers.