In the practical use of porous materials, pore blocking processes can occur leading to a decrease of the accessibility of the pore space. This percolation-type behavior is mainly influenced by the connectivity of the pore network. In order to characterize this property of porous media, the usefulness of a method is discussed which determines a value for pore connectivity with the help of digital image processing. Starting with a microphotograph of a prepared section of the porous sample, the proposed algorithm, in a first step, covers the pore space of the digitized image with convex areas, In the second step, it determines the number of convex areas connected to a given one. The mean number of the neighbouring areas is said to be the measure of the connectivity of a pore network. To check the usefulness of the method, the connectivities of different pore textures are measured and the results are evaluated critically.