The optical absorption edge of In-4(P2S6)(3) layered crystals is studied in the temperature range 77-355 K. In the spectral range of direct optical transitions, the absorption edge is of Urbach shape. Electron-phonon interaction result in the smearing, of energy bands and, consequently, in appearing of Urbach absorption tails. The temperature variation of the optical pseudogap E-g(*) and the absorption edge energy width w are well described in the Einstein model. Strong anisotropy of the absorption edge spectral position and shape, as well as of electron-phonon interaction, is revealed. (C) 2002 Elsevier Science Ltd. All rights reserved.