Thermal evaporation was used to prepare nickel (Ni) doped cadmium selenide thin films in different proportions (0, 1 and 3) wt.% on glass substrates at room temperature. According to XRD examination, all films possessed a polycrystalline hexagonal structure, with the (002) plane as the ideal orientation. According to AFM analysis, the average particle size decreases as the amount of doping increases, showing that the distribution of grains has become more uniform. The transmission and distortion ratios of the films were measured to learn more about their optical properties, which revealed that the (CdSe) films' transmittance decreased as the Ni films were doped, respectively. Additionally, it was discovered that all produced films had absorption coefficients larger than (α >104 𝑐𝑐𝑚𝑚- 1 ) and that the value of this coefficient rises with increasing doping. The films exhibited all direct optical energy gaps, according to the findings (CdSe). As the doping fraction decreased, the gap values decreased from 1.72 eV to 1.62 eV.