A numerical model was proposed to simulate the capillary micro-flow through a fiber bundle. The capillary pressure was predicted by the Young-Laplace equation and the corresponding optimal values of permeability were found by a trial-and-error method. The empirical Kozeny constants which are dependent on fiber volume fraction were recommended for the prediction of permeability. A numerical model was proposed to simulate the capillary micro-flow through a fiber bundle. The empirical Kozeny constants which are dependent on fiber volume fraction were recommended for the prediction of permeability.