Zinc oxide is a wide band gap semiconductor of the II-VI semiconductor group which are used in emerging applications for transparent electrodes in liquid crystal displays in energy saving or heat protecting windows. Solvothermal synthesis, which has been well developed in the last decade, is a versatile method for controlling the morphology of the well-defined nanostructure materials (e.g., metals, metal oxides, and MOFs). In this aspect, we have an attempt to prepare pure ZnO and Ca doped nanocrystals by solvothermal method. The structural property of the prepared sample was analysed by power X-ray diffraction. The prepared samples were optically characterized by UV –vis spectral analysis. The results were reported and discussed here