Turkish oil shales are convenient for obtaining oil products and carbonaceous matter. The process that was designed in this work gave a capability of controlling unwanted volatile materials. Carbonization was shown to be successful and optimum conditions of 1.5 h of heating at 775 K were obtained. The samples of oil shale specially the Goynuk oil shale, where successfully demineralized. Seyitomer and Goynuk oil shales could be classified as immature type 1 kerogen on the basis of the distribution of elemental H/C and O/C ratios.