Many countries depend on energy, and it is advisable to generate energy from renewable energy sources. Pork and duck fat are residues that can be used to generate biodiesels. Thus, this research evaluated the obtaining of biodiesel from the oil extracted from pork and duck fat. For the production of biodiesel, the transesterification method was used, mixing different proportions of oil, catalyst and alcohol at a temperature of 60 °C. The results indicated that the best proportion to obtain biodiesel from pork and duck waste was 250 mL of oil, 50 mL of alcohol (methanol) and 1.5 g of catalyst (potassium hydroxide). The lower calorific value was also higher in the duck fat biodiesel (M8) with values of 7433 Cal/g and biodiesel from pork fat (M2) presented values of 7448 Cal/g. Both biodiesel obtained met the quality requirements established in ASTM D6751 standard and could be used as alternatives to common diesel.