Cd1-x,MnxS nano-crystal line films (0 <= x <= 0.5) were formed on glass substrates by thermal evaporation technique at room temperature (300 K). AFM studies showed that all the films were in nano-crystalline form with the grain size varying in the range between 36 and 58 nm and exhibited hexagonal structure of the host material. The lattice parameters varied linearly with composition, following Vegard's law in the entire composition range. The nanohardness and Young's modulus decreased sharply with 'Mn' content upto x = 0.3 and increased with high Mn content. (c) 2007 Elsevier B. V. All rights reserved.