Cu2ZnSnS4 (CZTS) thin films have been grown by reactive pulsed laser deposition in H2S atmosphere, combining the alternate ablation from the metallic (Cu) and alloyed (ZnxSn) targets at room temperature. The morphological, structural and optical properties of as grown CZTS thin films with varying compositions as well as upon annealing in N-2 atmosphere are investigated by Rutherford backscattering spectrometry, X-ray diffraction, Raman spectroscopy and optical spectrophotometry. The chemical bonding in the "bulk" of the CZTS films is elucidated via hard X-ray photoemission spectroscopy measurements. The formation of the good quality stoichiometric polycrystalline CZTS films is demonstrated upon optimization of the growth parameters. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.