In thisstudy, themethods of replacing CO 2 and thermal stimulation are integrated toincrease the production efficiency of methane from gas hydrates and reduce theoperational time of this process. Experiments are carried out at constantpressure of methane at 60 bar, and three various injection pressures of carbondioxide at 40, 45 and 50 bar. We also have three temperatures for CO 2 at 5.5, 8 and 10 ° C. The purpose is to find the optimal temperatureand pressure for replacing methane gas by carbon dioxide in gas hydratecrystals. Meanwhile to improve the heat transfer and replacement process theuse of silica and ZnO nanoparticles gas has been investigated. Sample gases areanalyzed by the GC device. Finally, the temperature and pressure conditionsin the various experiments are compared with each other, and the optimumconditions are determined. The results show that at a constant pressure, with 2° C increase in temperature, the process of replacing carbon dioxide in methanehydrates improves. But an increase in temperature, more than 4 ° C, causes themethane hydrate to decompose. And also the use of ZnO nanoparticles can improvethe replacement process. Keywords:gas hydrate, replacement of methane with carbon dioxide, thermal stimulationmethod