Reducing emissions associated with the combustion of hydrocarbon fuels and increasing the consumption of biofuels represents an urgent economic and environmental task. Biodiesel is an alternative to petroleum diesel fuel and is widely used as a commercial fuel blendstock. In this regard, it is important to study the feasibility of using biodiesel obtained from various raw materials as a blendstock of commercial diesel fuels, as well as to identify optimal ratios of biodiesel fuel/petroleum diesel fuel. The addition of even small amounts of biodiesel has a positive effect on the environmental properties of the fuel. In the present study, we synthesize biodiesel fuel from sunflower, corn, and rapeseed oils by the reaction of interesterification using ethyl alcohol as an interesterifying agent and sodium hydroxide as a catalyst. The composition and properties of the synthesized biodiesel fuels were determined. Blends of biodiesel/petroleum diesel fuel with 5, 10, 15, 20 vol.% biodiesel blend content were prepared followed by determination of their composition and properties. It was found that the addition of biodiesel fuel increases the density, viscosity, and self-ignition of the resulting fuel, at the same time as decreasing the sulfur content and making the fractional composition heavier. This effect is directly proportional to the concentration of biodiesel in the blend. The effect of reducing the limiting filterability temperature of the blend fuel by the addition of biodiesel was revealed, with its maximum achieved at different concentrations of biodiesel synthesized from sunflower, corn, and rapeseed oils. For the production of a summer commercial diesel fuel, we recommend blends of 10vol.% biodiesel fuel, derived from any of the vegetable oils under study, and 90vol.% petroleum diesel fuel.