Chitin is the second most abundant natural polymer after cellulose. It occurs as a component of crustacean shells, insect exoskeletons, fungal cell walls and plankton. In this work, chitin was extracted from crab shells waste by chemical method. It includes two major steps such as demineralization and deproteinization step. These two steps were crucial for the elimination of calcium carbonate and other minerals as well as protein which are present in the shells. To extract the successive chitin, the sequence of these two treatment steps were varied in these experiments. In this study, the chemical compositions of crab shells waste were analyzed by X-ray fluorescence (XRF), the resultant chitins were characterized and analyzed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR).