In order to demonstrate the analysis of chlorine (Cl) in oil, a calibration curve has been constructed according to ASTM D4929 method except that a rhodium anode tube has been used. Five standard samples were prepared in accordance with the norm to construct a calibration curve. This method proposes the use of net peak intensities; hence a background position was chosen. The counting time on the Cl peak and the background position are identical. From a concentrate product which contained 1000 ppm of Chlorine, a mother solution was prepared by diluting this concentrate with Isooctane. This mother solution was then used to prepare several samples with various Chlorine concentrations.