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The present invention discloses a distillation process for producing benzene, toluene, and xylene from crude benzene, which comprises a 4-column continuous distillation process including a pre-separation column system, an extractive distillation column system, a solvent recovery column system, and a benzene-toluene column system； The distillation process includes a heat exchange network design, in which the lean solvent from the bottom of the solvent recovery tower is sequentially used as the intermediate reboiler of the extractive distillation column, the reboiler of the pre-separation column, the reboiler of the benzene-toluene column, the intermediate reboiler of the solvent recovery tower, the feed preheater of the extractive distillation column, and the feed preheater of the benzene-toluene column for heat exchange. After this heat exchange, the lean solvent can be directly returned to the extractive distillation unit for reuse. This method is used for the refining and separation of crude benzene after catalytic hydrogenation. This distillation process and heat exchange network operate under mild conditions of low temperature and pressure, enabling hierarchical recovery and utilization of energy; in industrial applications, it offers advantages such as lower investment costs, reduced energy consumption, and a simpler process flow. Compared to distillation processes using the Krupp-Koppes method or similar approaches, the investment is reduced by 1/3 to 1/2, and energy consumption is lowered by 20 to 30%. It is currently being applied in two projects with a capacity of 50,000 tons each; one of them is nearly ready for operation after its design has been completed, while the other is still in the stage of process package design. Feel free to ask. hgq_tju@163.com