The problem of the high cost of the materials that used in different devices and the increasing demand for new substituted materials has enhanced the interest in replacing these materials by semiconductors materials to be used. In this study the chemical structure and optical properties of Zinc oxide samples were studied to be used as substituted material using X-Ray Fluorescence. Zinc metal, Zinc sulphide, zinc sulphate and commercial oxide in a powdered form were collected from different areas in Khartoum State, Sudan. These samples were subjected to heat treatment at 1000OC in furnace under ambient oxygen for 3, 6 and 9 hours respectively except the commercial oxide sample which was used as a control. These samples were pressed in a pellets form using press machine under 15 tons pressure. The spectra are recorded at an incident angle θ 45± 5 with respect to the surface of the sample and revealed that the spectrum Zn Kα is 8.638 KeV for all samples and Zn k β is 9.572 KeV lines and signals from the Cu source of the x-ray tube. Peaks of ZnO samples obtained from Zn annealed at 1000oC for 3 hours and from ZnS annealed at 1000oC for 9 hours represented sharp and smooth peaks, while the other samples represented sharp and rough peaks. Among the samples annealed at 1000oC for 3 ours, ZnO obtained from ZnSO4 recorded the highest intensity value (9.9x103a.u) followed by ZnO (8.1x103a.u) obtained from Zn annealed at 1000oC for 9 hours and then ZnO (7.8x103a.u) sample obtained from Zn annealed at 1000oC for 6 hours.