Reducing the crude oil viscosity is important for the oil production and transportation. The micro-nanotechnology of viscosity reduction associated with electric field is found to be universal, working for all kinds of crude oil, including asphalt base crude oil and paraffin base crude oil. Especially at low temperature, the electric field is extremely efficient: in a couple of seconds after the electric field is applied, the viscosity is reduced substantially, making the flow rate in a pipeline more than double. The technology consumes very little energy and will be very useful for both off-shore and on-shore crude oil production and transportation. (C) 2013 Elsevier Ltd. All rights reserved.