Extensive usage of micro/nanoscale porous media in various applications, require comprehensive understanding of fluid transport in those systems, such as in the unconventional oil-reservoirs, micro/nano-membrane technologies and lab-on-a-chip applications. The frequently employed transport calculations in literature do not consider any effects related to size or shape of the pore. Instead, dynamically similar flow systems assumed by the porosity of a given medium that an “ability of flow” definition named permeability is employed for a given solid/liquid couple based on the corresponding porosity. However, in such small-scales, liquid flow characteristics diverge from continuum behavior and non-equilibrium effects should be considered to estimate the transport. Furthermore, geometrical parameters of pore structures and networks should be considered, in addition to porosity, for a proper characterization. Hence, pore scale analyses of fluid flow were performed by solving Navier-Stokes equation numerica lly with finite element method in a representative elementary volume. Permeability values were calculated based on the Darcy’s Law, at different pore-to-throat-size ratios, porosities, and velocity slips whose range determined by a literature review. Permeability showed a strong dependence on pore-to-throat-size ratios, and slip conditions. Using the permeability of pores across a wide range of conditions, the Kozeny-Carman (KC) relation was re-considered. An extended phenomenological Kozeny Carman model to predict micro/nanoscale liquid transport as a function of porosity, pore-to-throat size ratio, and slip length was developed. The pore-to-throat-size ratio and slip effects were found substantial on transport, which was successfully predicted by developed model. Keywords and Phrases: Velocity slip length, permeability, porosity, pore-to-throat size ratio, computational fluid dynamics