A great emphasis is placed on searching for efficient sources to produce renewable fuels due to the actual trends in avoiding the use of fossil resources to mitigate the environment’s deterioration. Thus, the use of waste from the food or wood industry for the production of biofuels is widely researched and may contribute to sustainable general development. Rendered fat and Fischer-Tropsch waxes are high-energy materials which could be used for the pyrolysis reaction. Therefore, in this study, the effect of reaction parameters and feedstock composition on the distribution of the pyrolysis products has been examined. The experiments were carried out in a nitrogen atmosphere in a multi-shot pyrolizer instrument equipped with GC-FID. First, the influence of the temperature was examined at 785, 800, and 815 °C. The highest yield to olefins was observed at 815 °C. The effect of triglycerides and paraffins contents (0−100% with 10% ramp) in the feedstock on the product composition was investigated at 815 °C. The gas chromatography analyses revealed that the feedstock composition did not significantly affect the product composition due to the high temperature and the long linear chain structure similarities between the free fatty acids and Fischer-Tropsch waxes.