Modularized steel combined bookshelf

The invention relates to a modularized steel combined bookshelf which comprises at least one bookshelf unit, wherein each bookshelf unit comprises a rectangular frame structure consisting of a base, atop plate and two side plates; a group of holding plates are of a frame structure and are distributed vertically; assembling connection holes for fixedly connecting adjacent bookshelf units are formed in end surfaces of the side plates; and the assembling connection holes of every two adjacent bookshelf units are fixed through connecting parts. The bookshelf units can be prefabricated in a largescale in a factory, components and elements of each bookshelf unit are independently packaged, then the bookshelf is relatively simple, convenient and rapid to assemble; since a plurality of bookshelfunits are fixedly connected to assemble an overall combined bookshelf, compared with the prior art that the bookshelf is assembled according to sizes, the combined bookshelf provided by the inventiondoes not need specific plan