Catalytic decomposition of methane (CDM) is an environmentally friendly technique to produce hydrogen and nano-carbon materials without greenhouse gas emissions. To compare the catalytic activity and hydrogen productivity of various active metals in the CDM reaction, experiments were performed by synthesizing Fe–Al, Co–Al, and Ni–Al catalysts through the co-precipitation method. According to the hydrogen production calculation for each catalyst, the Ni-based catalyst exhibited the best hydrogen production at a reaction temperature of 600 ℃. It could be attributed to the influence of the strong metal–support interaction on the catalytic activity. Based on the Ni–Al catalyst, which showed better hydrogen production than the other active metals, the activity and hydrogen production of the CDM process were analyzed according to different process factors. 90 L/gcat of hydrogen was produced through the optimization of process factors such as reduction temperature, reduction time, spatial velocity, methane flow, and gas addition.