(Objective) To address the issue of the stable oil-water "transition layer" in polymer flooding produced fluid, which is formed by the synergistic effects of resins, asphaltenes, mechanical impurities, and polymers, (Methodology) this study analyzed the composition of this transition layer and revealed the inhibition mechanism of its main components on the electric dehydration process. A synergistic treatment scheme combining an electric field and chemical agents was proposed, and its electro-chemical synergistic destabilization mechanism was demonstrated. (Results) The results indicated that 500 mg/L of SYP-416 was significantly effective in mitigating the "electric field collapse" phenomenon caused by the solid phase, reducing the water content in oil to 1.32% after 1 hour of electric dehydration; whereas 500 mg/L of SYP-417 was relatively effective for the "electric field collapse" caused by the oil phase, decreasing the water content to 3.26% after 1 hour. (Conclusion) The two agents effectively treated their respective phases, leading to a significant decrease in electric current without electric sparking inside the electric dehydrator. Furthermore, the synergistic mechanism of the chemical agents and the electric field significantly enhanced the mass transfer efficiency of interfacial water molecules and solid particles, achieving efficient demulsification and separation. The research findings have been applied in oilfield operations, confirming that this technology can restore the operational stability of the electric dehydrator.