One step fabrication of the three dimension (3D) fibrous structure of Collagen-g-poly(MMA-co-EA)/Nylon6 was investigated by controlling the experimental conditions during coaxial electrospinning. This 3D fibrous structure is the result of interactions of two polymeric systems with a varied capability to be electrostatically polarized under the influence of the external electric field; the solution with the higher conductivity into the inner spinneret and the solution with the lesser conductivity into the outer capillary of the coaxial needle. This set-up was to obtain bimodal fiber fabrication in micro and nanoscale developing a spatial structure; the branches growing off a trunk. The resultant 3D collagen-based fibrous structure has two distinguished configurations: microfibers of 6.9 ± 2.2 µm diameter gap-filled with nanofibers of 216 ± 49 nm diameter. The 3D fibrous structure can be accumulated at an approximate height of 4 cm within 20 min. The mechanism of the 3D fibrous structure and the effect of experimental conditions, the associated hydration degree, water uptake and degradation rate were also investigated. This highly stable 3D fibrous structure has great potential end-uses benefitting from its large surface area and high water uptake which is caused by the high polarity and spatial orientation of collagen-based macrostructure.