A dielectric fluid composition containing of 60% to 63% in weight of mono-unsaturated fatty acid, of 20% to 23% in weight of di-unsaturated fatty acid, of 5% to 7% in weight of tri-unsaturated fatty acid, and of 6% to 8% in weight of saturated fatty acid, such that the dielectric fluid is free of antioxidants and/or external additives and has the following properties: a dielectric strength of 40 kV to 70 kV at a separation of 2 mm, a dielectric constant of 2.5 to 3.1 at 25° C., and a dissipation factor of 0.05% to 0.15% at 25° C. The dielectric fluid composition can be obtained by a combination of 95.5% to 99.25% in weight of at least one high oleic vegetable oil, of 0.25% to 1.5% in weight of grape seed oil, of 0.25% to 1.5% in weight of sesame seed oil, and of 0.25% to 1.5% in weight of rice bran oil.