Recently, the Paris Agreement which many nations agreed to limit greenhouse gas emissions, has come into effect. According to the agreement, many of the compounds currently used in the refrigeration sector are scheduled for phase out due to ozone depletion concerns and/or contributions to global warming. There is current interest in developing working fluids with low global warming potential (GWP). One such fluid is 2,3,3,3-tetrafluoroprop-1-ene (R1234yf). Although the thermophysical properties are critical for the selection of the potential refrigerant, only a few studies have been conducted on the thermophysical properties of refrigerant mixtures containing R1234yf. In this work, we focused on the viscosity of R32 and the binary mixture of R32 + R1234yf. The liquid viscosity of R32 and binary mixture of R32 + R1234yf were presented over the temperature ranges of (263 to 350) K and (263 to 360) K at pressures up to 30 MPa using the vibrating wire viscometer. The measurements of mixtures containing the mole fraction (0.2448, 0.4108, 0.6086 and 0.8356) of R32 were carried out. The overall uncertainties of these results were ±2.0 %. The experimental results of the pure R32 and the mixture were correlated with hard-sphere scheme. The average absolute deviations between the experimental results and the correlations were 0.28 % for R32 and 0.69 % for R32 + R1234yf, and the maximum absolute deviations were 0.92 % and 2.09 %, respectively. Comparisons between measurements of this work and literatures were also presented.