Thermal diffusion factor has been calculated for dipolar binary fluid mixtures modeled as a two-center Lennard-Jones plus point dipole using the non-equilibrium molecular dynamics simulation. Thermal diffusion factor is an increasing function of the dipole moments of two components in isotopic model mixtures. Thermal diffusion factor in dipolar fluids is also a sensitive function of the electrostatic part of the intermolecular interactions. (C) 2007 Elsevier B.V. All rights reserved.