With obesity on the rise, there has been great interest in identifying functional foods that can alter metabolism to mitigate obesity. One nutraceutical that has gained attention is green coffee bean extract (GCBE), sourced from raw coffee beans. Research has shown that it has a variety of biological effects including antioxidant and anti-inflammatory properties and regulation of lipid and glucose metabolism. It has been reported that the main polyphenolic compound in GCBE, chlorogenic acid (CGA), is likely responsible for these effects. However, GCBE had not yet been studied in Drosophila melanogaster, the fruit fly. Drosophila are a noted model organism as flies and humans share 60% of disease related genes and similar mechanisms for metabolic regulation. In this study, flies were treated with 0, 1, or 2 mg/mL GCBE and physiological parameters and gene expression were assessed. GCBE significantly reduced fat accumulation in flies, in part by a reduction in food intake. Flies were also treated with an isoform of CGA, 5-caffeoylquinic acid, but this treatment did not change fat accumulation. Overall, this study serves as a foundation for further research on GCBE to determine its potential mechanism of action. This may inform the use of GCBE as a nutraceutical for the treatment of obesity.