Abstract: A systematic study has done to investigate the thin films of chemically deposited CdSe and Tl doped thin films. The deposition has been carried out in an alkaline medium at 70 0C for about 90 minutes. Characterization of thin films were done using X-ray diffraction (XRD), scanning electron microscope (SEM) optical absorption, electrical conductivity and thermoelectric techniques. These study reveals that films are polycrystalline in nature with cubic structure. The electrical conductivity of the order of 10-5 ( cm)-1 and an optical energy gap of 1.55 eV to 2.01 eV with a direct allowed type of transitions have been noticed. The thermoelectric power measurements shows n-type conduction mechanism for pure CdSe and doped CdSe thin films.