Abstract: The quasi-cold start-up technology for modified crude oil in Dongying-Linyi parallel oil pipeline has been adopted. The analytical results on test data abtained from the laboratory simulation experiment and industrial experiment on BEM-3 oil modifier have showed that BEM-3 oil modifier has got a perfect stability on anti-shear and repeated heating and viscosity reduction/pour point depression efficiency for the oil transported. The paper describes the preheating process of pipeline by means of twice regular pumpings and once reverse pumping with water. In accordance with the feature of quasi-cold start-up technology, the economy and safety analysis have been carried out.