The development of scientifically engineered fibrous porous networks has been gaining momentum due to their potential advantages in a wide spectrum of end-uses, including but not limited to, filtration, heat exchangers, fuel cells, acoustic applications, and biological transfer phenomena. Fluid flow through fibrous structures is the determining factor in the engineering of these materials for applications in various manufacturing and process industries. Precise de?nition of traort properties of ?brous porous networks necessitates greater understanding of their 3D fiber orientation and porosity at the micro-scale. In order to investigate the effect of fiber orientation and porosity on fluid flow behavior, a Matlab-based program capable of producing ?brou structure with variou ?ber diameters, porosities, thicknesse and 3D ?ber orientatio wa developed. The in-plane fiber orientation was varied and its effect on through- and in-plane permeability of layered structures was investigated. The through- and in-plane permeabilities of such structures were obtained by solving the Stokes equations. The presentation of the results for each type of ?brous network structure and ?ow con?guration was preceded by brief outlines of the pertinent literature, and followed by a discussion on the performance of CFD results toghether with empirical, analytical and numerical models. It was established that at logarithmic scale there exists a linear relation between the permeability and porosity of the structure for The permeability in the through- and in-plane directions was shown to be different and the anisotropic nature of the geometry creates anisotropic permeability. It was found that, the in-plane fiber orientation does not affect the through-plane permeability. It was also established that the in-plane fiber orientation has a significant effect on in-plane permeability of layered structures. The results indicated that in-plane permeability reduces with the increase in the deviations of the ?bers axis from flow direction. Acceptable agreement between the results and previously published ?ndings was observed.