The rapid deficiency of fossil fuel resources encourages the research community to discover the sustainable alternate fuel, in order to overcome the fuel cost and also meet the stringent emission norms. In this connection, the current investigation explores the influence of cobalt chromate with significant potential of citronella biofuel for CI engine applications. In present investigation, the synthesized cobalt chromate nano additive blended with citronella biofuel with the help of magnetic stirrer for a period of 15 to 20 minutes on a volume basis. In this experimentation, various blend contractions are prepared as follows as 50ppm, 100ppm, and 150ppm to run the engine. The outcome results explore that the 100ppm cobalt chromate dispersion in biofuel has a significant increase in brake thermal efficiency as 2.9% than raw citronella biofuel. The engine run at full load condition, when compared to citronella biofuel the establishment of output emission is decreased marginally as 26% for HC and 9% for smoke opacity. However, the presence of nano additives in biofuel emitting the traceable amount of oxides of nitrogen, towards the exhaust gas at part load to full load conditions, corresponding to the reaction rate of nano additive.