Three recent physically based models (Lennard-Jones, free volume, thermodynamic scaling) for representing the viscosity of sulfur hexafluoride (SF 6 ) are discussed together with two models (friction theory and Enskog 2σ) that have been recently applied to this fluid. The experimental database employed for adjustment (1562 data points) considers a large temperature (225.18 to 473.15K) and pressure intervals (0.0264 to 51.21MPa). The absolute average deviation is 3.8% for the Lennard-Jones model (one parameter), 1.7% for the free volume model (three parameters) and 1.5% for the thermodynamic scaling model (six parameters). Thus, it is shown that when physically based approaches are employed, a limited number of parameters is sufficient to represent accurately the shear viscosity of SF 6 . Furthermore it has been confirmed, using the thermodynamic scaling approach, that the repulsive steepness of the SF 6 interaction potential is higher than usually found for fluids composed by non polar spherical molecule.