The invention belongs to the technical field of automatic machinery, and particularly relates to a flexible independent unit workbench with an assembly device. The flexible independent unit workbench comprises a support, wherein an upper-layer rolling workbench and a lower-layer rolling workbench are arranged on the support; material supply transfer plates are connected to the upper-layer rolling workbench in a rolling manner; material supply transfer plates are connected to the lower-layer rolling workbench in a rolling manner; jacking mechanisms located between the upper-layer rolling workbench and the lower-layer rolling workbench are fixedly connected to the support; openings for enabling the jacking mechanisms to longitudinally stretch are formed in the upper-layer rolling workbench; a plurality of hangers are arranged on the upper-layer rolling workbench; the hangers are inverted-U-shaped; the assembly device is arranged on the hangers; the assembly device comprises an assembly seat plate; a plurality of assembly heads are arranged on the assembly seat plate; and the assembly seat plate is connected with a position adjustment system. The flexible independent unit workbench has the following advantages: the assembly device arranged on the hangers is capable of carrying out assembly machining on products during a conveying process, thus the production efficiency is increased, and the flexible independent unit workbench is reasonable in overall design.