Abstract: The objective of this study is to compare the combustion, emissions, and engine performance of two different modified fuels. The oxygenated nanoparticles (CeO2 and Al2O3) were homogeneously mixed into B20 with an ultra sonicator at a specific ratio of 50,100 ppm to explore the potential of nanoparticles as a flexible booster in physiochemical properties of biodiesel. The generated nanoparticle fuel samples are then put to the CRDI VCR engine at various loads (3,6,9,12 kg): B20+50 Al2O3, B20+100 Al2O3, B20+50 CeO2, B20+100 CeO2. The different nano fuel's engine capabilities, combustion, and emissions are then contrasted with biodiesel, diesel, and one another. Performance-wise, BTE was 11.39% higher and SFC was 13.74% lower than B20 for B20+ 50 Al2O3 at high load. The cylinder pressure and heat release rate for B20+50 Al2O3 are respectively 16.77% and 21.48% greater at full load than for B20. In terms of hazardous emissions, B20+50 Al2O3 reduced CO emissions by 15.06% compared to B20, while B20+50 CeO2 reduced HC emissions by 50% compared to diesel at peak load. Additionally, at engine peak loads, B20+50 CeO2 Reduces NOx by 18.29% compared to B20. The findings suggest using nano fuel as a diesel oil replacement fuel.