In the dry reforming of methane with CO2, coke formation in the catalyst during the reaction is the most serious problem. As a coke resistant reforming catalyst, Ni/Al2O3 nanosheets were synthesized by a solvothermal method. The synthesized nanosheet catalysts demonstrated highly stable methane conversion, although the amount of deposited carbon was similar to that in Ni/Al2O3 with a random morphology that deactivated rapidly. The critical effect of nanosheet morphology has been demonstrated on the coke tolerance of the nickel-based dry reforming catalyst.