The purpose of this study was to compare used tyre pyrolysis oil blends with conventional diesel fuel when fueling a diesel engine. The test fuel was characterized based on the density, viscosity, boiling point, calorific value, sulphur content, flash point, carbon residue, ash, and water content,. The thermo physical and chemical characteristics were also evaluated for raw oil, refined oil before and after distillation. The fuel was then blended with diesel and used in an internal combustion engine. Blends of 20%, 40%, 60% and 75% by volume were investigated. This exhaust emissions and performance data were collected for steady state operation at different load conditions. It has been found from the performance and emission analysis that the usage of oil blends with diesel in direct injection CI engines has shown similar performance and reduced emission as that of same CI engine operated in pure diesel.