The shale oil reservoir in the second member of Kongdian formation（Ek2）of Cangdong Sag in Dagang oilfield exhibits significant effects during the initial stage after primary fracturing，but the energy and production decline rapidly in later stages. Furthermore，the produced fluids are severely emulsified，resulting in a reduction of shale oil recovery，and increase of pipeline transportation resistance and development challenges. Through systematic analysis of the physicochemical properties of Ek2 shale oil，emulsification characteristics of shale oil-water and their influencing factors，this study revealed the reasons and mechanisms of shale oil-water emulsification，and proposed methods to mitigate emulsification-induced viscosity enhancement. The results showed that the Ek2 shale oil contained over 20% wax content on average with a pour point exceeding 35 ℃. Moreover，the high content of heavy hydrocarbons favored the occurrence of emulsification phenomenon. Nitrogen-containing polar components（e.g.，resins and asphaltenes）and wax crystals facilitated the formation of water-in-oil（W/O）emulsions during the flow of shale oil and water， resulting in emulsification-induced viscosity enhancement phenomenon. The viscosity of shale oil increased first and then decreased with increasing water content，peaking at 50%—70% water content with viscosity values 3.23—7.45 times that of dehydrated crude oil. The stability of W/O emulsions formed during shale oil-water emulsification process was enhanced by increasing emulsification temperature，water phase salinity，and intruding fracturing fluid composition. Additionally，complex O/W/O multiple emulsions generated when the emulsified shale oil was re-emulsified，further increasing the viscosity of system. However，introducing a small amount of emulsifier during the re-emulsifying process enabled phase inversion from W/O to oil-in-water（O/W）emulsion，thus effectively reducing the viscosity of shale oil and improving fluidity. Consequently， it was necessary to consider the physicochemical properties of shale oil as conducting water injections and energy enhancement for shale oil reservoirs. The development of high-activity surfactants for shale oil stimulation would be a focus for subsequent process design and product research.