The gas viscosity of difluoromethane was measured using an oscillating disk viscometer of the Maxwell type from 298.15 to 423.15 K at pressures up to 10 MPa. The results were fitted to an empirical equation as a function of temperature and density. Intermolecular force constants of the Lennard-Jones 12-6 potential were determined. In addition, the experimental density was compared with the calculated values from various equations of state previously reported.