This paper describes the diet fed to chicks of two pairs of New Zealand Falcons nesting in forested habitat. Both pairs fed their chicks almost exclusively on birds weighing less than 85 g. No mammals or reptiles were recorded in the diet; invertebrates represented an insignificant component. Both pairs caught more medium-sized birds (20-35 g) than large (70-646 g) or small birds (5-14 g). Falcons showed no size-based selection; rather, the size of prey that falcons selected to feed to chicks closely matched their abundance. Sixteen species of birds were identified in the diet, and comprised 44% of the bird species present in the home ranges of both pairs. About half of the birds in the diet were introduced species.