Thermal conductivity measurements for organic molecules are difficult and time-consuming. In this study, the thermal conduction of liquid aldehydes and ketones was simulated using nonequilibrium molecular dynamics, and the thermal conductivity at different temperatures was calculated. The deviation between the calculated values and the experimental data of thermal conductivity is less than 4.86%. By decomposing the heat flux, we found that thermal energy is primarily transferred through the torsion angle, angle bending, Coulomb interaction, and kinetic energy in the liquid state. Moreover, as the molecular chain grows, the thermal energy transmitted through the nonbonded interaction decreases, and the thermal energy transmitted through the intramolecular bonded interaction increases, which indicates a significant relationship between the mechanism of heat transfer and the molecular structure. Using molecular dynamics simulation, this research offers a preliminary understanding of the contributions of microscopic heat transfer to the thermal conductivities of liquid aldehydes and ketones.