The present work investigates the effect of precursor concentration (m c) on the structural, optical, morphological and electrical conductivity properties of In 2 S 3 thin films grown on amorphous glass substrates by nebulized spray pyrolysis (NSP) technique. The mixed phase of cubic and tetragonal structure of In 2 S 3 thin films at higher concentration has been observed by X-ray diffraction pattern. The reduced strain by increasing the precursor concentration increased the average crystallite from 17.8 to 28.9 nm. The energy dispersive analysis by X-ray (EDAX) studies confirmed the presence of In and S. The transmittance, optical direct band gap energy, Urbach energy and skin depth of In 2 S 3 films have been analyzed by optical absorption spectra. The better conductivity and mobility noticed at m c = 0.15 M are explained by carrier concentration and crystallite. Better optical and electrical conductivity behaviour of In 2 S 3 thin film sample proposes for effective solar cell fabrication.