High catalyst activity plays an important role in the safe and efficient operation of methane-steam reforming reactors. Since transport resistance limits the effectiveness factor in the reactor to values much less than unity, increasing the catalyst surface area increases its activity. Using a mathematical model of a terrace wall reactor, the effect of catalyst shape on performance of the reactor has been studied. Considering different parameters of catalyst effectiveness factor, reaction gas temperature, reactor pressure drop and mechanical strength, it has been shown that a multichannel cylinder is a good choice among different alternative catalyst pellet shapes. Compared to a standard spherical shape, a multichannel cylinder gives 10% less total pressure drop and its effectiveness factor is almost three times higher.