This article is devoted to the study of thermal conductivity of nanofluid. A nanofluid is a liquid in which nanometer-sized solid particles are dispersed. These particles are called nanoparticles. Nanofluids have new promising thermophysical properties compared to conventional heat transfer fluids. Thermal conductivity is one of the main thermophysical properties of a liquid. Thermal conductivity is of great importance in processes where heat transfer and fluid flow occur. The article presents well-known theoretical models for determining the thermal conductivity of nanofluid. A brief description of these models is given. Some experimental work on determining the thermal conductivity of various nanofluids is considered. A computational study of the effect of aluminum oxide (Al2O3) and silicon dioxide (SiO2) nanoparticles on the change in thermal conductivity of a nanofluid has been performed. A comparative analysis of known computational models and experimental data is carried out. The accuracy of the calculated models is determined by determining the thermal conductivity of the nanofluid.