This work is a review of the papers devoted to investigation of the thermal conductivity in single crystal and polycrystalline UO2 and (U,Pu)O2 using molecular dynamics simulations, with inter-atomic interactions described by different potential models. Two main approaches are used to calculate the thermal conductivity by MD. In the first approach the thermal conductivity is given by the autocorrelation function of the energy current based on the Green-Kubo relations. In the second approach the thermal conductivity is defined from the energy current and temperature gradient using the Fourier law. The main results of the molecular dynamics simulation of the heat conductivity of the UO2 and (U,Pu)O2 are presented.