The Azure-rumped Tanager is omnivorous and feeds on fruit and arthropods. It has been observed feeding on fruit of various species of Ficus (Moraceae), on Rhamnus discolor (Rhamnaceae), Trema micrantha var. strigillosa (Ulmaceae), mistletoe Phoradendron heydeanum (Verbanaceae), Perrottetia longistylis (Celastraceae), Miconia sp. (Melastomataceae), Cecropia obtusifolia (Cecropiaceae), Chomelia brachypoda (Rubiaceae), Cestrum sp. (Solanaceae), Urera sp. (Urticaceae) (Eisermann et al. 2011a). On Atitlán volcano, the encounter rate of Azure-rumped Tanager was positively correlated with the density of Ficus aurea trees, which produces large figs (15-20 mm diameter) as main food source (Eisermann et al. 2011a). Adults were also reported to feed on Lepidoptera larvae gleaned from leaves, and imagoes of sciarid flies (Diptera: Sciaridae) catched in sallying flights (Eisermann et al. 2011b).