The invention pertains to a method for processing of liquid hydrocarbon raw materials. The method includes preliminary pretreatment of a flow of raw materials and further processing with fractionation. The pretreatment is performed by forming a primary flow of liquid hydrocarbon with the characteristics of a straight tubular laminar flow and then directing that flow through a spiral tubing at a velocity the maximal value of which maintains laminarity of the laminar primary flow through the spiral tubing. The laminary primary flow is fractionated following the pretreatment. The invention has applications to the field of petroleum processing and may find application in the petroleum and petrochemical industries, and in the field of fuel power engineering.