The invention belongs to the technical field of building materials and in particular relates to a double undulated web slab steel box girder. The cross-section fracture shape is composed of a middle web slab, an upper flange and a lower flange which are integrated, wherein the upper flange is parallel to the lower flange, a double web slab is vertically located between the upper flange and the lower flange, the double web slab is arranged symmetrically and takes a honeycomb structure, the web slab and the flange slabs adopt one side fillet weld to connect, the web slab is an undulated web slab whose length direction are periodically repeated evenly or unevenly, and the undulated cross section takes circular arc angle trapezoid and sinusoidal curve. The product can replace products such as normal welded box steel girders, hot rolled H-shaped steel, I-shaped steel and the like, has wider usage compared with the products, and can realize maximization and can be used in the special fields and special places including the building of bridges with large spans, the manufacture of ships and the like.