Forest plantations may have detrimental effects on biodiversity. However, these plantations are widely used to restore degraded habitats, yet their contribution to restoring functional diversity remains largely unknown. We assessed vegetation structure, resource availability, and bird abundance, as well as bird morphological, behavioral, life history, and functional diversity in 35-year-old monospecific protected Andean alder (Alnus acuminata) forest plantations in the Central Andes range at elevations between 2,400 and 2,800 m, to determine if plantation structure and resource availability favor bird functional diversity. We compared our findings to a 35-to 45-year-old secondary forest that had naturally regenerated. We found similarities in bird functional diversity but different functional composition between the Andean alder plantation and secondary forest. The bird life history, behavioral, and morphological traits from the secondary forest were more heterogeneous than those from the plantation. In addition, standing dead trees in the Andean alder plantation promoted bird functional diversity and the presence of birds in the plantation interior. Overall, vegetation structure and understory resource availability of Andean alder plantations appear sufficient to enable bird functional diversity partially resembling that of secondary forests in the region.