The invention belongs to crude oil gradual distillation energy-saving equipment and a process method. According to a connecting mode of crude oil gradual distillation, the equipment comprises a flash distillation tower, a primary distillation tower, a primary decompression tower, a shallow decompression tower and a deep decompression tower; an electrical desalting device and a heat exchange network are arranged between the flash distillation tower and the primary distillation tower; a heat exchange network or a primary decompression furnace is arranged between the primary distillation tower and the primary decompression tower; a shallow decompression furnace is arranged between the primary decompression tower and the shallow decompression tower; and a deep decompression furnace is arranged between the shallow decompression tower and the deep decompression tower. Through gradual heating, crude oil is gradually heated to be close to the condensed temperature and vaporized so as to substantially reduce the nonreversibility of heating and cooling; simultaneously, as light components are gradually drawn out, the residual materials can realize vaporization under the lower pressure; therefore, the materials can enter the decompression and distillation stage after passing through the primary distillation tower; the gradual decompression technology of primary decompression, shallow decompression and deep decompression is adopted to reduce the heating temperature of raw materials, lighten the load of a heating furnace and remarkably improve the processing capacity of the system.