The present invention discloses a viscous oil emulsion preparation method comprising mixing of viscous oil, an emulsifier, a stabilizer and water at first temperature to form an oil-in-water emulsion and cooling of the oil-in-water emulsion to second temperature, wherein the viscosity of the viscous oil at the first temperature is not more than 500mPa.s, and the viscosity of the viscous oil at the second temperature is not less than 2000mPa.s. The present invention also discloses a viscous oil conveying method, and the method includes preparation of the viscous oil into the oil-in-water emulsion by the viscous oil emulsion preparation method and conveying of the oil-in-water emulsion at the second temperature. The viscous oil emulsion prepared by the viscous oil emulsion preparation method has good stability, and can meet the requirements of long-distance transport.