AbstractGaSe‐crystals have a layer structure and a band gap of 2 eV. The electrode behaviour of p‐type specimens has been investigated by measuring current‐voltage curves in the dark and at illumination, by determining capacity‐voltage correlations and by studying the spectral dependence of the photocurrents. It has been found that the surface orientation besides surface perfection has an extraordinary influence on the results reflecting the anisotropy of the electronic properties of such a material. The differences in photocurrent yield for light incident either normal or parallel to the layer planes are in good agreement with the optical constants for these directions. The differences in reactivity at cathodic bias are discussed on the basis of the calculated electron distributions in the valence bands of this material combined with the assumption that surface states with acceptor character exist in the energy range below the conduction band edge.