Six kinds of dendritic polyether surfactants were synthesized with different proportions of propylene oxide and ethylene oxide using phenol-amine resin as a precursor. The surface tension and demulsification performance of these polyether surfactants were studied. It shows that the six dendritic polyethers behave like typical surfactants. The results reveal that these new types of surfactants show interesting demulsification properties towards the simulated emulsions used in our work. The structure of the polyethers can influence the demulsification performance, of which the main factor is the molecular block. The demulsification mechanism of these dendritic polyethers was studied using single-droplet protocol, and the dynamic data of drainage time, half life time, and rupture rate constant obtained are consistent with the demulsification law of the six dendritic polyethers. (C) 2010 Elsevier B.V. All rights reserved.