In this study, sunflower oil was investigated for biodiesel production. Sunflower is one of the leading oil seed crop, cultivated for the production of oil in the world. It has also been considered as an important crop for biodiesel production. Seeds for biodiesel production were procured from local farmers of Attock and Rawalpidni divisions. Electric oil expeller was used for the extraction of crude oil. Base catalyzed transesterifiction process is applied for optimum yield (80%) of biodiesel. Fuel properties of sunflower oil biodiesel were compared with American Society for Testing and Materials (ASTM). Engine efficiency of biodiesel with reference to power, efficiency and consumption of biodiesel blends (B100, B20 and B5) were determined. It was concluded that sunflower oil is one of the option for biodiesel production at a large scale depending on its mass cultivation.Keywords: Sunflower oil, transesterification, biodiesel, energ