Cu2ZnSnS4 (CZTS) thin films were prepared by ball-milling, coating and sintering. Structural, morphological, compositional, and optical properties of CZTS thin films were analyzed by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM) and UV–vis spectrophotometer respectively. The results indicated that CZTS phases were observed at 200°C and the crystallinity was improved with the temperature rising. When sintered over 450°C, the CZTS thin films had relatively dense structure, large grains (34.7–36.9nm). And the optical band gap of the thin film sintered at 450°C was 1.44eV.