We quantified the diet of the Chilean Hawk (Accipiter chilensis) by analyzing 495 prey remains collected during two breeding seasons (2001–2002 and 2002–2003) in an Andean Nothofagus forest of Nevados de Chillán, northern Patagonia. The diet was almost exclusively birds (97.8% of all prey remains), with relatively few rodents (1.6%) and insects (0.6%). At least 19 vertebrate species composed the prey remains (1 small mammal and 18 bird species), with Austral Thrush (Turdus falcklandii), White-crested Elaenia (Elaenia albiceps), Black-chinned Siskin (Carduelis barbata), Fire-eyed Diucon (Xolmis pyrope), and Thorn-tailed Rayadito (Aphrastura spinicauda) being the most common. All identified vertebrate prey are known to use forest habitats; 47% (n = 9) are forest specialists. Prey that inhabit both forest and shrublands accounted for 82% of the remains, and 18% of prey remains were of forest specialists. Our results indicate that during the breeding season, Chilean Hawks in Nevados de Chillán are pre-eminent, bird-eating predators that feed primarily on forest-dwelling birds.