In this paper, Changqing crude oil was emulsified under pressure in different dissolved gas environments (CO2, CH4, N2) by using crude oil emulsifier with pressure dissolved gas. The solubility (Rs) , water separation rate (fv), interfacial tension (γ), interfacial modulus of elasticity (εd), viscosity of dissolved gas crude oil (μ) and apparent viscosity of dissolved gas crude oil emulsion (μap) were measured by means of solubility measurement device, emulsion stability analysis device, interfacial tension tester and high pressure rheometer. The results show that the presence of oil⁃water interfacial film inhibits the migration of gas from the outer phase to the inner phase to a certain extent, so that the solubility of the dissolved gas oil emulsion is less than the solubility of the internal and external phases. Under the environment of dissolved CO2, because of the minimum interfacial tension between oil and water, the best emulsification effect is obtained, and the W/O emulsion droplets with pressure are the most compact. Under the environment of dissolved CO2, because of its minimum interfacial tension between oil and water, the smallest droplets are formed in W/O emulsion and the emulsifying effect is the best. At the same time, due to the elastic modulus of oil⁃water interface is the largest, the emulsion system is the most stable, and the viscosity ratio of emulsion system is the most obvious than that of crude oil system. In contrast, in the environment of N2 dissolution, the stability of the emulsion system is poor, and it is easy to demulsify.