The Kozeny-Carman equation is a traditional permeability-porosity relationship which has been used in many models of real problems related to flows in porous media. Inspite of this, some limitations of this well-known equation has motivatedthe conception of different versions, specialized for particular applications. In the present article, we deduce a three-parameter Kozeny-Carman equation obtained from a fractal structure involving the specific surface and the tortuosity oft he porous medium. Here, a theoretical analysis indicates that the new equation is capable to generalize several models existent in the literature. Besides, parameter estimations fitting experimental data of different materials show that the present model can be used to describe the relationship between permeability and porosity of many materials, such as sand stones, sisal fiber mat and glass fiber fabrics. Crown Copyright (C) 2010 Published by Elsevier Ltd. All rights reserved.