Estimating the concentration of sulphur compounds in crude oil and its products such as gasoline and kerosene is necessary because of environmental legislation and determinants developed by government organizations regulating sulphur levels in oil and its derivatives. Sulphur compounds found in crude oil and its products are a major problem, causing many environmental and health risks as a result of the use of gasoline as fuel for cars and kerosene as fuel for household heaters, resulting in the emission of these compounds in the form of oxides, affecting the environment and health. This study was conducted to estimate the concentration of sulphur compounds in crude oil and distillation products represented by gasoline and kerosene and to show how different the concentration of sulphur compounds in crude oil is than in gasoline and kerosene. In this study, gas chromatography technology was used. This method applies to distillation products, gasoline fuel, kerosene and other petroleum liquids. This study was conducted in basra oil company's quality control laboratories to estimate the concentration of sulphur compounds in crude oil, gasoline and kerosene.