The present paper reports the electrical conductivity and optical bandgap measurements of a-Si,S:H films in the alloy range (S/Si ratio 0.51*10(-2) to 4.07*10(-2)) as a function of deposition temperature. The a-Si,S:H samples were prepared by conventional plasma-assisted CVD through decomposition of H2S and SiH4 mixtures using substrate temperatures up to 500 degrees C. When the deposition temperature is raised From 230 tu 500 degrees C, the concentration of S in the films decreases. The main effect of S alloying is a strong increase in IR mode at approximately 480 cm(-1) which corresponds to Si-S bond. The optical bandgap decreases dramatically with deposition temperature. The conductivity is found to be activated with the fermi level moving towards the conduction band edge up to S/Si ratio of 0.51 * 10(-2) and as the S/Si ratio further increases an increase in activation energy is observed which may be due to the increase in bandgap. The value of sigma(o) indicates conduction in extended states.