In this paper, electrostatic demulsification and dehydration experiments were conducted on water-in-crudeoil emulsions with three kinds of water-cuts based on the independently established experimental system for electric-field demulsification and dehydration whose electric field parameters(waveforms especially) are adjustable. And the effects of electric-field waveform, frequency, voltage and water cut on demulsification characteristics of water-in-crude-oil emulsions were investigated systematically by ta...