The article discusses thermal properties of synthetic ester admixed with nanoparticles. The analyzed thermal properties were: thermal conductivity λ, kinematic viscosity υ, density ρ, specific heat cp, and the thermal expansion factor β- all obtained by means of measurements. On the basis of these, the authors calculated the heat transfer factor α, which determines the ability of the liquid to heat transport. The authors used nanoparticles of fullerene C60 and titanium oxide TiO₂. The analysis of the thermal properties was done for the temperatures of 25, 40, 60 and 80 °C. The authors analyzed the impact of nanoparticles C60 and TiO₂ on thermal properties of synthetic ester. They proved that fullerene C60 in principle had no influence on heat transfer factor α of the ester, while titanium oxide TiO₂ had some positive influence on the factor, the value of which increased about 1⁻3%.