The basic aim of this study was to examine the usability of plastic municipal and medical waste as an alternative source to diesel engines. For this study; waste plastic materials, obtained from Adana Metropolitan Municipality dumping site and medical wastes from Adana State Hospital were used. Waste plastics were transformed to waste plastic fuel by thermal cracking. Municipal and medical waste plastic fuels without bleaching process were blended with diesel fuel at volumetric ratios of 10%, 20% and 50%. Fuel properties of waste plastic fuels and its blends with diesel fuel were analysed in accordance with the standards of American Society for Testing and Materials (ASTM) methods. In addition to fuel properties, engine performance and exhaust emission tests of waste plastic fuel and diesel fuel blends were performed.