Abstract: Gas-oil/water two-phase emulsion is usually encountered in a lot of chemical engineering fields, such as crude oil production, natural gas and oil transportation. For the oil/gas/water multiphase flow in tubes, it is essentially important in engineering application and academic study to understand the hydrodynamic characteristics of oil/water emulsion under the disturbance of gas. However, the existing numerical oil- water two-phase emulsion viscosity models are not suitable for the oil-gas-water three-phase flow in tubes. So, after substantial experiments on oil-gas-water three-phase flow in vertical upward tubes,this paper purposes oil-water emulsion viscosity models of slug flow in vertical pipes. Based on these models, gas, oil-water emulsion flow in a vertical upward pipe show three hydrodynamic characteristics, namely, non-Newtonian fluid characteristics with gas disturbance thickening, non-Newtonian fluid characteristics with gas disturbance weakening. For oil/water-gas three-phase slug flow in vertical upward tubes, errors of the pressure-drop model based on the oil/water emulsion viscosity models, which were set up this paper, are in the allowable range between predictive values and experimental data.