Abstract: The mass production system disclosed herein provides a method for producing highly aromatic petroleum pitch, comprising, preheating a liquefied petroleum residuum to a temperature of 450.degree.-520.degree. C. by passing the same through a tubular heater for 0.5-15 minutes, feeding the preheated residuum into a reaction vessel, thermally cracking the same by introducing an inert gas heated to a temperature of 400.degree.-2,000.degree. C. through a heating furnace into the reaction vessel for direct contact with the residuum for 0.5-10 hours, and adjusting to be coincident the ratio of the number of feeding flow lines for the preheated residuum from the tubular heater into the reaction vessels to the total number of reaction vessels with the ratio of the charging time .theta.C required for charging one reaction vessel with one feeding flow of preheated residuum to the total time .theta.T required for carrying out one batch of the thermal cracking in one reaction vessel.