This study described the diet of the orange-rumped agouti Dasyprocta leporina in French Guiana. Five food types were identified in stomach contents: seeds, pulp, fibre, leaves and animal matter. D. leporina ate mainly fruit parts, pulp and seeds, although the ingestion of animals, leaves and fibre was not negligible. Food intake differed from one season to another. D. leporina was a pulp-eater (64.8% pulp in March) when fleshy fruit was plentiful and available on the ground (February–May). The level of pulp ingestion was globally in accordance with fruit production. When food resources were low (June–September), D. leporina consumed seeds and cotyledons (73.0% seeds in August) as well as animal (16.4% in July) and to a lesser level, plant parts. By focusing on other food categories, and particularly seeds, it gets nutritious food thus avoiding starvation between June–September. Large proportions of seeds appeared in stomach contents and correlations between seed quantities and ground production were negative and significant; D. leporina seemed to react to environmental factors such as rainfall and fruit production.