Abstract: Resin and asphaltene were separated from Daqing crude oil and were dissolved in decane. The interfacial viscoelasticity was investigated by applying the controlled stress model of oscillatory ring interfacial rheometer CIR-100. The effects of resin, asphaltene contents in decane, pH values, and demulsifiers in aqueous phase on interfacial viscoelasticity were studied. It was shown the interfacial viscoelasticity of water/decane containing asphaltenes or resins is of the order of 4 higher than that of water/decane, and the interfacial viscoelasticity increased with increasing resin and asphaltene concentrations in decane.When the pH value in aqueous phase was about 7,interfacial elasticity approached a maximum. Demulsifers in aqueous phase could obviously reduce interfacial viscoelasticity and interfacial tension.