Graphene oxide (GO) paper, as a precursor of the graphene paper, is an appealing candidate as a structural material for modern technology due to its high specific strength and stiffness. In order for its full potential to be harnessed in various applications, the relation between its mechanical properties and structure needs to be investigated systematically. Herein, we have synthesized our GO solution using modified Hummers’ method, fabricated the various thickness of GO papers, characterized GO solution and papers by spectroscopic and other methods, and measured the mechanical properties of GO papers with different thicknesses (0.5m ~100m), such as the Young’s modulus, fracture strength, fracture strain, and fracture toughness by using inversed bulge test and uniaxial tensile test methods. The Young’s modulus, fracture strength and fracture toughness were found to decrease with increasing thickness, with the first two exhibiting the differences of factor of four. In contrast, the fracture strain increased with thickness slightly. Our transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) results show that the changes in the mechanical properties of the GO papers with thickness are due to variations in their inner structures and surface morphologies such as crack formation and surface roughness. Thicker GO papers are weaker because they contain more voids that are produced during the vacuum assisted filtration fabrication process. Surface wrinkles and residual stress were found to result in increased fracture strain. This dissertation provides deeper insight into the relation between the structure and the mechanical properties of the artificially fabricated layered structures of GO papers and improved guidelines or design reference for the use of GO-based thin film materials in mechanical structures. In addition, here, we report a one-pot post-processing method for easily modulating properties of GO membranes through vapor phase metal-impregnation used in conventional atomic layer deposition (ALD) process. ALD is introduced as an important technique for tailoring GO thin films for a variety of applications because as-made GO is electrical insulating which largely interferes with the technological progress in some field. Upon impregnating a small amount of transition metal impurities into soft materials with hydrogen bonds significantly improves such the materials’ mechanical stabilities. Tiny amount of Zn impregnated by ALD triggered mechanical as well as electrical properties enhancement (~ 20% greater in stiffness and ~ 103 times higher in conductivity) in the GO membrane. It is strongly believed that this method can be a surprisingly simple and extremely useful mean to tailor the properties of the GO membranes as well as other nano-porous materials. Finally, large area (A4 size) and conductive rGO paper was fabricated and patterned on demand, by reduction and assembly on the Al foil at the same time. Through the oxidation and reduction reaction of the metal substrates and GO, GO is converted into rGO. Further to control the volume of the GO solution, we could get the different thickness of rGO paper. Stacked GO samples with sandwich structure were fabricated using epoxy. The mechanical properties of GO papers are various with different fabrication methods.