ABSTRACT Alternative fuels offer various advantages over traditional fossil fuels, including the fact that they are recyclable, sustainable, Contribute to energy independence, and reduce emissions. Renewable fuels such as Compressed natural gas and biodiesel were used in this study. Natural gas is an appealing and appealing fuel because of its vast availability, low Cost, and Clean-burning qualities. The use of biodiesel, namely mustard oil biodiesel, aids in making it Cleaner and more Cost-effective. The present study aims to reduce tailpipe emissions from diesel engines using dual-fuel Combustion, which employs a Combination of fossil and renewable fuels. An experimental analysis was Carried out to evaluate the effectiveness and tailpipe emissions of a twin-cylinder diesel engine fueled by pilot Mustard oil biodiesel (MOB) and CNG, with variations in the rate of CNG flow and time of pilot injection. According to the findings, advanced pilot injection timing (PIT) at 24°CA bTDC (degree Crank angle before top dead Center) and using a lower rate of CNG flow (0.2 kg/h) resulted in the highest brake thermal efficiency (31.21%), while brake specific fuel Consumption decreased by nearly 10% at this setting. Increasing pilot fuel injection to 24°CA bTDC and maintaining a modest rate of CNG flow at 0.2 kg/h in a dual-fuel model decreased NOx emissions by 26% when Compared to diesel alone mode, but resulted in a minor rise in CO emissions. The Current study may aid in the Conversion of a significant number of small to mid-segment diesel engines used in irrigation and the industrial sector in the Indian subcontinent. The study helps in minimizing NOx emissions while also lowering import fossil fuel Costs.