To our knowledge, this study is the first to report on the nutritional characterization, bioactive compounds and antioxidant activity of Amazonian G. macarenensis fruit. The fatty acid profile was determined using a high performance liquid chromatography analysis. The total phenolic content and antioxidant activity were determined using Folin Ciocalteu’s method and by radical scavenging activity, respectively. Moreover, a cluster analysis was carried out in order to classify the G. macarenensis fruit oil according to its fatty acid profile. Seven Fisher linear discriminant functions were obtained from the discriminant analysis. These models allow one to classify new fruits on the basis of their fatty acid profile. A high value for total lipids was obtained (53.57%). Its main components were palmitic and oleic acid. The TPC value (156.49 ± 2.62 mg GAE/Kg of oil) obtained from the G. macarenensis fruit pulp oil is higher than what was reported for some olive oil and Brazilian mango oil varieties.