Curassows (Cracidae) are important components of the avian biomass in neotropical frugivorous bird communities. However, their feeding habits and ecological role remain unclear. We identified the diet of wild Yellow-knobbed Curassow (Crax daubentoni) based on analyses of feces and direct observations from November 2001 to July 2002 in a tropical dry forest in central Venezuela. We also analyzed stomach contents from specimens collected in different localities throughout the Llanos region. The diet of curassows included fruits (41 and 49% of dry weight in feces and stomach contents, respectively), seeds (15 and 48%), leaves (39 and 0.7%), minerals (stones, earth; 4.3 and 1.1%), and small proportions of flowers, roots, fungus, seedlings, and invertebrates (insects, Order Coleoptera), each <1% of total dry weight. Curassows fed on 26 plant species from 21 families. When food resources for frugivores are scarce during the dry season (Nov–Apr), 47–50% of the diet was a single species (Guazuma ulmifolia, Sterculiaceae) indicating this species can be critical for curassow survival. An increase in consumption of leaves and invertebrates was observed in the rainy season (May–Jul). Most seeds observed in feces (93%; n = 5,408; range = 1–10 mm) were intact suggesting that curassows could have an important role as seed dispersers in this tropical ecosystem.