Abstract: The terrestrial shale oil in Dagang Oilfield has a high pressure drop rate, low productivity, serious wellhead paraffin deposition, and short paraffin removal cycle in the later stage of dewatering with flowing. In severe cases, it will lead to the end of flowing or well shutdown. In order to prolong the flowing period of shale oil wells, the dewatering effect of different sizes of pipe string was calculated by referring to the dewatering experience of shale gas velocity string. The structure of the temporarily sealing off soluble bridge plug was improved, and the laboratory test was carried out. Auxiliary dewatering technology of shale oil was developed. The technology utilized coiled tubing unit to run the temporarily sealing off soluble bridge plug under pressure to sealing off the pressure in the well. The optimized auxiliary dewatering string was run into the wellbore by conventional workover operation to bring the oil well to flowing. The field application shows that the technology can improve the wellhead temperature and flow rate, alleviate the influence of paraffin deposition, reduce the pressure drop rate of dewatering with flowing, prolong the self-flowing period by 95–100 days, and improve the enhance oil recovery of shale oil wells. The research results provide a new technical approach for the beneficial development of shale oil in the later stage of dewatering with flowing.