The Turpentine oil has getting wider attention in recent times due to many significant benefits. In this present study, 20% Turpentine oil has been blended with 80% diesel fuel by volume. A novel cetane improver called SC5D has been doped with 20% biofuel at 2.5% and 5% concentrations. All the properties of all the blends are evaluated and it has been identified that the 5% of cetane improver has increases the fuel density. All the fuel samples have been tested in a single cylinder CRDI diesel engine under different pilot injection rate of 15% and 30% at 600 bar injection pressure. For the higher NOx emission condition, the 10% EGR has also been applied. The experimental study revealed that the addition of cetane improver with biofuel blends has shown comparable performance behaviours at all concentrations. Furthermore, the unburned hydrocarbon and smoke emissions are remarkably lower for biofuel blends at both the injection rate with cetane improver addition. Significant reductions has been noticed by 10% EGR addition for PI15% rate at 2.5% and 5% concentrations without much defect in other emissions. All the combustion behaviours have shown comparable behaviours with cetane improver addition and 10% EGR implementation with biofuel blends. Therefore, it can be concluded that the novel cetane improver could be used as additive with Turpentine oil in diesel engine applications. © 2019 Elsevier Ltd