Recycling process of waste cotton fabrics into value added products is still limited. Cotton fabrics are made of cotton fiber, which is a high cellulose source and it can be converted into microcrystalline cellulose (MCC). In this research, MCC was prepared by dissociation of waste cotton fabric using gamma irradiation with various radiation doses in dried phase and in wet phase by 35 % H2O2 solution. The properties of the prepared MCC were investigated and compared with standard Avicel PH101 MCC. The results from FTIR spectra and X-ray diffraction patterns show that the obtained MCC has typical similarity to commercial MCC. X-ray diffraction analysis showed that the crystallinity percentage (%Cr) was increased while crystallite size was decreased through gamma irradiation. At the same dose, degree of polymerization (DP) and solubility in water in dried phase, i.e. 135; 5.46 % were higher than wet phase irradiation i.e. 123; 4.38 %. Degree of polymerization and solubility in water decreases with increasing total irradiation dose. The investigated physicochemical properties of the obtained MCC conform to the European Pharmacopoeia requirements. The results indicated that waste cotton fabrics have a great potential as a low cost MCC raw material and can lead to many applications.