This study aimed to thermodynamically evaluate the performance of biodiesel generated from African palm mixed with diesel at variable concentrations used in an internal combustion engine to analyze its viability as an alternative energy source. Thus, we characterized the mixtures of different concentrations and modeled the parameters in Aspen HYSYS ® , characterizing the mixtures B0, B10, B20, B50, and B100 based on the Peng-Robinson-Stryjek-Vera (PRSV) model, followed by determining the most optimal mix according to the restrictions considered. Then, we simulated the KOHLER KDI 2504M engine, making the power curves of the engine with each of the mixtures evaluated, observing behaviors similar to the literature, where we found that torque and power decrease as they increase. The percentage of biodiesel has a maximum value of 10%, where the speeds at which the maximum torque and power occur are the same for all the mixtures evaluated. In the same way, we evaluated the most optimal mixture obtained with the multi-objective optimization in the engine model B69 due to its properties that guarantee good behavior in the internal combustion engine. Keywords: Biodiesel, Diesel, KOHLER, Aspen HYSYS, PRSV DOI： https://doi.org/10.35741/issn.0258-2724.58.6.17