Cotton is a hot climatic industrial plant commonly planted on both the tropical and subtropical regions of the world. Four different genotypes of cotton, Aşkabat-100 (G. barbadense ), Coker-312 and Stoneville-468 (G. hirsutum ), were studied for callus induction. The cotton anthers extracted from immature flower drafts (cotton gins) were used as explants. Cotton anthers taken from different length immature cotton combs  were used as explants. After samples taken from cotton anthers of different lengths (2, 3, 4, 5 mm) were subjected to sterilization with different NaOCl concentrations (% 10, % 20 ve % 30) prepared in sterilized glass containers for surface sterilization, the immature anthers found in the obtained were extracted and placed in feeding media with various amounts of different hormones to induce callus formation.  After the seeding is done, lids of the petri dishes have been closed and to prevent the air inflow and outflow were covered with  parafilms, then the petri dishes were left for dark in the climate room for about 30-60 days. The experiments were performed with repetitions of 3. Seeding was done every three days and the callus size and the regeneration rates that resulted from 5 week dark environment incubation were determinedOnce the anthers were transferred to the induction media, one-hour cold (4°C) shock and one-hour hot shock (40°C) were applied to them, they were kept in dark for a while and were left for collaganase in climate room at 16/24 light regime. All experiments in this study were performed in triplicates.  As the result of the experiments, the highest rate of callus formation was observed in Cooker 312 supplemented with 2mg/mL of NAA and 2 mg/L of BA hormones. Callus formation was also higher in the condition where NAA was used than the media supplemented with 2,4-D. Additionally, callus formation showed better results in cold and hot shock applied anthers compared to the ones that were not shocked.