Abstract: In order to more accurately investigate the characteristics of these vortices, such as leakage vortices and separation vortices, in the flow path of oil and gas mixing pumps when transporting media under high viscosity conditions, the Euler-Eulerian nonlinearity model of homogeneous flow was used to analyze the gas phase distribution and vortex distribution in the oil-gas mixed pump, and rigid rotating vorticity was used to characterize the vortex intensity. The results show that the existence of the gas phase greatly affects the distribution of streamlines on the blade surface in the impeller channel of a multiphase pump. Under partial design conditions, the gas phase is mainly concentrated in the latter half of the pressure surface when the viscosity is small, and the gas phase is less distributed in the latter part of the pressure surface when the viscosity is large. The distribution of the leakage vortex under different working conditions is in good agreement with the gas phase distribution. Under the partial design condition, the aggregation degree of the gas phase at the tail of the flow channel is proportional to the viscosity, but the local gas phase aggregation in the flow channel is improved under the large flow condition. In addition, due to the low turbulent viscosity and more shear vortices in the flow channel under high viscosity conditions, the vorticity distribution is more accurate when considering rigid rotation. The research results can serve as a theoretical reference for the optimal design of oil-gas mixed pumps.