Abstract: To study the influence of gathering pipeline and equipment corrosion products on crude oil dehydration, the simulated iron corrosion products including FeS, FeCO₃ and their subsequent oxidation products Fe(OH)₃ were prepared by coprecipitation method, and their effects on the stability of simulated emulsion were studied. On this basis, the dehydration effect of ultrasonic-assisted demulsification technology was analyzed. The results show that the Zeta potential (the absolute value is about 30 mV) of FeS and Fe(OH)₃ is so high as to greatly promote the stability of water/crude oil emulsion, while FeCO₃ may lead to the difficulty in dehydration of crude oil at high temperature. Under appropriate conditions, the dehydration rate could be significantly improved by ultrasonic and demulsifier. The influence of corrosion products on emulsion stability was verified by the experiment, and it is suggested to strengthen the anticorrosion of gathering pipeline and equipment, so as to effectively improve the processing effect of crude oil.