The antimony tri-sulphide (Sb₂S₃) films were prepared by thermal evaporation technique. Four thicknesses (300, 521, 643 and 789 nm) were investigated. X-ray diffraction (XRD) analysis showed the amorphous structure of Sb₂S₃ films. Optical analyses revealed that Sb₂S₃ films exhibited optical energy gap between (1.98–1.16 eV) relaying on the film thickness. The films absorption coefficient was found to be higher than 2 × 10⁴ cm⁻¹(above its related optical energy gap) which makes these films reliable absorbers in photovoltaic applications. Optical constants were analyzed using Swanipole's method. The dark dc conductivity measurements of Sb₂S₃ thin films were conducted in the temperature range 298–503 K. The conduction mechanize was analyzed via Mott's variable -range hopping in three dimensions model. The correlated conductivity mechanize with increasing film thickness changed from extended